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Duolingo - Wikipedia

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class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Early_history"> <div class="vector-toc-text"> <span class="vector-toc-numb">1.1</span> <span>Early history</span> </div> </a> <ul id="toc-Early_history-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Funds" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Funds"> <div class="vector-toc-text"> <span class="vector-toc-numb">1.2</span> <span>Funds</span> </div> </a> <ul id="toc-Funds-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Features_and_media" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Features_and_media"> <div class="vector-toc-text"> <span class="vector-toc-numb">1.3</span> <span>Features and media</span> </div> </a> <ul id="toc-Features_and_media-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Products_and_services" class="vector-toc-list-item vector-toc-level-1"> <a class="vector-toc-link" href="#Products_and_services"> <div class="vector-toc-text"> <span class="vector-toc-numb">2</span> <span>Products and services</span> </div> </a> <button aria-controls="toc-Products_and_services-sublist" class="cdx-button cdx-button--weight-quiet cdx-button--icon-only vector-toc-toggle"> <span class="vector-icon mw-ui-icon-wikimedia-expand"></span> <span>Toggle Products and services subsection</span> </button> <ul id="toc-Products_and_services-sublist" class="vector-toc-list"> <li id="toc-Courses" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Courses"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.1</span> <span>Courses</span> </div> </a> <ul id="toc-Courses-sublist" class="vector-toc-list"> <li id="toc-Language_courses" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Language_courses"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.1.1</span> <span>Language courses</span> </div> </a> <ul id="toc-Language_courses-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Duolingo_Math" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Duolingo_Math"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.1.2</span> <span>Duolingo Math</span> </div> </a> <ul id="toc-Duolingo_Math-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Duolingo_Music" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Duolingo_Music"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.1.3</span> <span>Duolingo Music</span> </div> </a> <ul id="toc-Duolingo_Music-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Subscriptions" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Subscriptions"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.2</span> <span>Subscriptions</span> </div> </a> <ul id="toc-Subscriptions-sublist" class="vector-toc-list"> <li id="toc-Super_Duolingo" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Super_Duolingo"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.2.1</span> <span>Super Duolingo</span> </div> </a> <ul id="toc-Super_Duolingo-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Duolingo_Max" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Duolingo_Max"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.2.2</span> <span>Duolingo Max</span> </div> </a> <ul id="toc-Duolingo_Max-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Duolingo_for_Schools" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Duolingo_for_Schools"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.3</span> <span>Duolingo for Schools</span> </div> </a> <ul id="toc-Duolingo_for_Schools-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Duolingo_ABC" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Duolingo_ABC"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.4</span> <span>Duolingo ABC</span> </div> </a> <ul id="toc-Duolingo_ABC-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Duolingo_piano" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Duolingo_piano"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.5</span> <span>Duolingo piano</span> </div> </a> <ul id="toc-Duolingo_piano-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Duolingo_English_test" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Duolingo_English_test"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.6</span> <span>Duolingo English test</span> </div> </a> <ul id="toc-Duolingo_English_test-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Learning_model" class="vector-toc-list-item vector-toc-level-1"> <a class="vector-toc-link" href="#Learning_model"> <div class="vector-toc-text"> <span class="vector-toc-numb">3</span> <span>Learning model</span> </div> </a> <ul id="toc-Learning_model-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Business_model" class="vector-toc-list-item vector-toc-level-1"> <a class="vector-toc-link" href="#Business_model"> <div class="vector-toc-text"> <span class="vector-toc-numb">4</span> <span>Business model</span> </div> </a> <ul id="toc-Business_model-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Reception" class="vector-toc-list-item vector-toc-level-1"> <a class="vector-toc-link" href="#Reception"> <div class="vector-toc-text"> <span class="vector-toc-numb">5</span> <span>Reception</span> </div> </a> <button aria-controls="toc-Reception-sublist" class="cdx-button cdx-button--weight-quiet cdx-button--icon-only vector-toc-toggle"> <span class="vector-icon mw-ui-icon-wikimedia-expand"></span> <span>Toggle Reception subsection</span> </button> <ul id="toc-Reception-sublist" class="vector-toc-list"> <li id="toc-Effectiveness" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Effectiveness"> <div class="vector-toc-text"> <span class="vector-toc-numb">5.1</span> <span>Effectiveness</span> </div> </a> <ul id="toc-Effectiveness-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Criticism" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Criticism"> <div class="vector-toc-text"> <span class="vector-toc-numb">5.2</span> <span>Criticism</span> </div> </a> <ul id="toc-Criticism-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Awards" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Awards"> <div class="vector-toc-text"> <span class="vector-toc-numb">5.3</span> <span>Awards</span> </div> </a> <ul id="toc-Awards-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Image_and_brand" class="vector-toc-list-item vector-toc-level-1"> <a class="vector-toc-link" href="#Image_and_brand"> <div class="vector-toc-text"> <span class="vector-toc-numb">6</span> <span>Image and brand</span> </div> </a> <button aria-controls="toc-Image_and_brand-sublist" class="cdx-button cdx-button--weight-quiet cdx-button--icon-only vector-toc-toggle"> <span class="vector-icon mw-ui-icon-wikimedia-expand"></span> <span>Toggle Image and brand subsection</span> </button> <ul id="toc-Image_and_brand-sublist" class="vector-toc-list"> <li id="toc-Duolingo&#039;s_characters" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Duolingo&#039;s_characters"> <div class="vector-toc-text"> <span class="vector-toc-numb">6.1</span> <span>Duolingo's characters</span> </div> </a> <ul id="toc-Duolingo&#039;s_characters-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-In_popular_culture" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#In_popular_culture"> <div class="vector-toc-text"> <span class="vector-toc-numb">6.2</span> <span>In popular culture</span> </div> </a> <ul id="toc-In_popular_culture-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Duocon" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Duocon"> <div class="vector-toc-text"> <span class="vector-toc-numb">6.3</span> <span>Duocon</span> </div> </a> <ul id="toc-Duocon-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Duo&#039;s_Taqueria" class="vector-toc-list-item vector-toc-level-1"> <a class="vector-toc-link" href="#Duo&#039;s_Taqueria"> <div class="vector-toc-text"> <span class="vector-toc-numb">7</span> <span>Duo's Taqueria</span> </div> </a> <ul id="toc-Duo&#039;s_Taqueria-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Offices_and_workforce" class="vector-toc-list-item vector-toc-level-1"> <a class="vector-toc-link" href="#Offices_and_workforce"> <div class="vector-toc-text"> <span class="vector-toc-numb">8</span> <span>Offices and workforce</span> </div> </a> <ul id="toc-Offices_and_workforce-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-See_also" class="vector-toc-list-item vector-toc-level-1"> <a class="vector-toc-link" href="#See_also"> <div class="vector-toc-text"> <span class="vector-toc-numb">9</span> <span>See also</span> </div> </a> <ul id="toc-See_also-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Notes" class="vector-toc-list-item vector-toc-level-1"> <a class="vector-toc-link" href="#Notes"> <div class="vector-toc-text"> <span class="vector-toc-numb">10</span> <span>Notes</span> </div> </a> <ul id="toc-Notes-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-References" class="vector-toc-list-item vector-toc-level-1"> <a class="vector-toc-link" href="#References"> <div class="vector-toc-text"> <span class="vector-toc-numb">11</span> <span>References</span> </div> </a> <ul id="toc-References-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-External_links" class="vector-toc-list-item vector-toc-level-1"> <a class="vector-toc-link" href="#External_links"> <div class="vector-toc-text"> <span class="vector-toc-numb">12</span> <span>External links</span> </div> </a> <ul id="toc-External_links-sublist" class="vector-toc-list"> </ul> </li> </ul> </div> </div> </nav> </div> </div> <div class="mw-content-container"> <main id="content" class="mw-body"> <header class="mw-body-header vector-page-titlebar"> <nav aria-label="Contents" class="vector-toc-landmark"> <div id="vector-page-titlebar-toc" class="vector-dropdown vector-page-titlebar-toc vector-button-flush-left" > <input type="checkbox" id="vector-page-titlebar-toc-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-page-titlebar-toc" class="vector-dropdown-checkbox " aria-label="Toggle the table of contents" > <label id="vector-page-titlebar-toc-label" for="vector-page-titlebar-toc-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-listBullet mw-ui-icon-wikimedia-listBullet"></span> <span class="vector-dropdown-label-text">Toggle the table of contents</span> </label> <div class="vector-dropdown-content"> <div id="vector-page-titlebar-toc-unpinned-container" class="vector-unpinned-container"> </div> </div> </div> </nav> <h1 id="firstHeading" class="firstHeading mw-first-heading"><span class="mw-page-title-main">Duolingo</span></h1> <div id="p-lang-btn" class="vector-dropdown mw-portlet mw-portlet-lang" > <input type="checkbox" id="p-lang-btn-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-p-lang-btn" class="vector-dropdown-checkbox mw-interlanguage-selector" aria-label="Go to an article in another language. Available in 81 languages" > <label id="p-lang-btn-label" for="p-lang-btn-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--action-progressive mw-portlet-lang-heading-81" aria-hidden="true" ><span class="vector-icon mw-ui-icon-language-progressive mw-ui-icon-wikimedia-language-progressive"></span> <span class="vector-dropdown-label-text">81 languages</span> </label> <div class="vector-dropdown-content"> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li class="interlanguage-link interwiki-ar mw-list-item"><a href="https://ar.wikipedia.org/wiki/%D8%AF%D9%88%D9%88%D9%84%D9%8A%D9%86%D8%AC%D9%88" title="دوولينجو – Arabic" lang="ar" hreflang="ar" data-title="دوولينجو" data-language-autonym="العربية" data-language-local-name="Arabic" class="interlanguage-link-target"><span>العربية</span></a></li><li class="interlanguage-link interwiki-an mw-list-item"><a href="https://an.wikipedia.org/wiki/Duolingo" title="Duolingo – Aragonese" lang="an" hreflang="an" data-title="Duolingo" data-language-autonym="Aragonés" data-language-local-name="Aragonese" class="interlanguage-link-target"><span>Aragonés</span></a></li><li class="interlanguage-link interwiki-ast mw-list-item"><a href="https://ast.wikipedia.org/wiki/Duolingo" title="Duolingo – Asturian" lang="ast" hreflang="ast" data-title="Duolingo" data-language-autonym="Asturianu" data-language-local-name="Asturian" class="interlanguage-link-target"><span>Asturianu</span></a></li><li class="interlanguage-link interwiki-az mw-list-item"><a href="https://az.wikipedia.org/wiki/Duolingo" title="Duolingo – Azerbaijani" lang="az" hreflang="az" data-title="Duolingo" data-language-autonym="Azərbaycanca" data-language-local-name="Azerbaijani" class="interlanguage-link-target"><span>Azərbaycanca</span></a></li><li class="interlanguage-link interwiki-bn mw-list-item"><a href="https://bn.wikipedia.org/wiki/%E0%A6%A1%E0%A7%81%E0%A6%AF%E0%A6%BC%E0%A7%8B%E0%A6%B2%E0%A6%BF%E0%A6%82%E0%A6%97%E0%A7%8B" title="ডুয়োলিংগো – Bangla" lang="bn" hreflang="bn" data-title="ডুয়োলিংগো" data-language-autonym="বাংলা" data-language-local-name="Bangla" class="interlanguage-link-target"><span>বাংলা</span></a></li><li class="interlanguage-link interwiki-be-x-old mw-list-item"><a href="https://be-tarask.wikipedia.org/wiki/Duolingo" title="Duolingo – Belarusian (Taraškievica orthography)" lang="be-tarask" hreflang="be-tarask" data-title="Duolingo" data-language-autonym="Беларуская (тарашкевіца)" data-language-local-name="Belarusian (Taraškievica orthography)" class="interlanguage-link-target"><span>Беларуская (тарашкевіца)</span></a></li><li class="interlanguage-link interwiki-bg mw-list-item"><a href="https://bg.wikipedia.org/wiki/Duolingo" title="Duolingo – Bulgarian" lang="bg" hreflang="bg" data-title="Duolingo" data-language-autonym="Български" data-language-local-name="Bulgarian" class="interlanguage-link-target"><span>Български</span></a></li><li class="interlanguage-link interwiki-br mw-list-item"><a href="https://br.wikipedia.org/wiki/Duolingo" title="Duolingo – Breton" lang="br" hreflang="br" data-title="Duolingo" data-language-autonym="Brezhoneg" data-language-local-name="Breton" class="interlanguage-link-target"><span>Brezhoneg</span></a></li><li class="interlanguage-link interwiki-ca mw-list-item"><a href="https://ca.wikipedia.org/wiki/Duolingo" title="Duolingo – Catalan" lang="ca" hreflang="ca" data-title="Duolingo" data-language-autonym="Català" data-language-local-name="Catalan" class="interlanguage-link-target"><span>Català</span></a></li><li class="interlanguage-link interwiki-ceb mw-list-item"><a href="https://ceb.wikipedia.org/wiki/Duolingo" title="Duolingo – Cebuano" lang="ceb" hreflang="ceb" data-title="Duolingo" data-language-autonym="Cebuano" data-language-local-name="Cebuano" class="interlanguage-link-target"><span>Cebuano</span></a></li><li class="interlanguage-link interwiki-cs mw-list-item"><a href="https://cs.wikipedia.org/wiki/Duolingo" title="Duolingo – Czech" lang="cs" hreflang="cs" data-title="Duolingo" data-language-autonym="Čeština" data-language-local-name="Czech" class="interlanguage-link-target"><span>Čeština</span></a></li><li class="interlanguage-link interwiki-cy mw-list-item"><a href="https://cy.wikipedia.org/wiki/Duolingo" title="Duolingo – Welsh" lang="cy" hreflang="cy" data-title="Duolingo" data-language-autonym="Cymraeg" data-language-local-name="Welsh" class="interlanguage-link-target"><span>Cymraeg</span></a></li><li class="interlanguage-link interwiki-da mw-list-item"><a href="https://da.wikipedia.org/wiki/Duolingo" title="Duolingo – Danish" lang="da" hreflang="da" data-title="Duolingo" data-language-autonym="Dansk" data-language-local-name="Danish" class="interlanguage-link-target"><span>Dansk</span></a></li><li class="interlanguage-link interwiki-de mw-list-item"><a href="https://de.wikipedia.org/wiki/Duolingo" title="Duolingo – German" lang="de" hreflang="de" data-title="Duolingo" data-language-autonym="Deutsch" data-language-local-name="German" class="interlanguage-link-target"><span>Deutsch</span></a></li><li class="interlanguage-link interwiki-et mw-list-item"><a href="https://et.wikipedia.org/wiki/Duolingo" title="Duolingo – Estonian" lang="et" hreflang="et" data-title="Duolingo" data-language-autonym="Eesti" data-language-local-name="Estonian" class="interlanguage-link-target"><span>Eesti</span></a></li><li class="interlanguage-link interwiki-el mw-list-item"><a href="https://el.wikipedia.org/wiki/Duolingo" title="Duolingo – Greek" lang="el" hreflang="el" data-title="Duolingo" data-language-autonym="Ελληνικά" data-language-local-name="Greek" class="interlanguage-link-target"><span>Ελληνικά</span></a></li><li class="interlanguage-link interwiki-es mw-list-item"><a href="https://es.wikipedia.org/wiki/Duolingo" title="Duolingo – Spanish" lang="es" hreflang="es" data-title="Duolingo" data-language-autonym="Español" data-language-local-name="Spanish" class="interlanguage-link-target"><span>Español</span></a></li><li class="interlanguage-link interwiki-eo mw-list-item"><a href="https://eo.wikipedia.org/wiki/Duolingo" title="Duolingo – Esperanto" lang="eo" hreflang="eo" data-title="Duolingo" data-language-autonym="Esperanto" data-language-local-name="Esperanto" class="interlanguage-link-target"><span>Esperanto</span></a></li><li class="interlanguage-link interwiki-ext mw-list-item"><a href="https://ext.wikipedia.org/wiki/Duolingo" title="Duolingo – Extremaduran" lang="ext" hreflang="ext" data-title="Duolingo" data-language-autonym="Estremeñu" data-language-local-name="Extremaduran" class="interlanguage-link-target"><span>Estremeñu</span></a></li><li class="interlanguage-link interwiki-eu mw-list-item"><a href="https://eu.wikipedia.org/wiki/Duolingo" title="Duolingo – Basque" lang="eu" hreflang="eu" data-title="Duolingo" data-language-autonym="Euskara" data-language-local-name="Basque" class="interlanguage-link-target"><span>Euskara</span></a></li><li class="interlanguage-link interwiki-fa mw-list-item"><a href="https://fa.wikipedia.org/wiki/%D8%AF%D9%88%D9%84%DB%8C%D9%86%DA%AF%D9%88" title="دولینگو – Persian" lang="fa" hreflang="fa" data-title="دولینگو" data-language-autonym="فارسی" data-language-local-name="Persian" class="interlanguage-link-target"><span>فارسی</span></a></li><li class="interlanguage-link interwiki-fr mw-list-item"><a href="https://fr.wikipedia.org/wiki/Duolingo" title="Duolingo – French" lang="fr" hreflang="fr" data-title="Duolingo" data-language-autonym="Français" data-language-local-name="French" class="interlanguage-link-target"><span>Français</span></a></li><li class="interlanguage-link interwiki-ga mw-list-item"><a href="https://ga.wikipedia.org/wiki/Duolingo" title="Duolingo – Irish" lang="ga" hreflang="ga" data-title="Duolingo" data-language-autonym="Gaeilge" data-language-local-name="Irish" class="interlanguage-link-target"><span>Gaeilge</span></a></li><li class="interlanguage-link interwiki-gd mw-list-item"><a href="https://gd.wikipedia.org/wiki/Duolingo" title="Duolingo – Scottish Gaelic" lang="gd" hreflang="gd" data-title="Duolingo" data-language-autonym="Gàidhlig" data-language-local-name="Scottish Gaelic" class="interlanguage-link-target"><span>Gàidhlig</span></a></li><li class="interlanguage-link interwiki-gl mw-list-item"><a href="https://gl.wikipedia.org/wiki/Duolingo" title="Duolingo – Galician" lang="gl" hreflang="gl" data-title="Duolingo" data-language-autonym="Galego" data-language-local-name="Galician" class="interlanguage-link-target"><span>Galego</span></a></li><li class="interlanguage-link interwiki-ko mw-list-item"><a href="https://ko.wikipedia.org/wiki/%EB%93%80%EC%98%A4%EB%A7%81%EA%B3%A0" title="듀오링고 – Korean" lang="ko" hreflang="ko" data-title="듀오링고" data-language-autonym="한국어" data-language-local-name="Korean" class="interlanguage-link-target"><span>한국어</span></a></li><li class="interlanguage-link interwiki-hy mw-list-item"><a href="https://hy.wikipedia.org/wiki/Duolingo" title="Duolingo – Armenian" lang="hy" hreflang="hy" data-title="Duolingo" data-language-autonym="Հայերեն" data-language-local-name="Armenian" class="interlanguage-link-target"><span>Հայերեն</span></a></li><li class="interlanguage-link interwiki-hi mw-list-item"><a href="https://hi.wikipedia.org/wiki/%E0%A4%A1%E0%A5%81%E0%A4%93%E0%A4%B2%E0%A4%BF%E0%A4%82%E0%A4%97%E0%A5%8B" title="डुओलिंगो – Hindi" lang="hi" hreflang="hi" data-title="डुओलिंगो" data-language-autonym="हिन्दी" data-language-local-name="Hindi" class="interlanguage-link-target"><span>हिन्दी</span></a></li><li class="interlanguage-link interwiki-hr mw-list-item"><a href="https://hr.wikipedia.org/wiki/Duolingo" title="Duolingo – Croatian" lang="hr" hreflang="hr" data-title="Duolingo" data-language-autonym="Hrvatski" data-language-local-name="Croatian" class="interlanguage-link-target"><span>Hrvatski</span></a></li><li class="interlanguage-link interwiki-io mw-list-item"><a href="https://io.wikipedia.org/wiki/Duolingo" title="Duolingo – Ido" lang="io" hreflang="io" data-title="Duolingo" data-language-autonym="Ido" data-language-local-name="Ido" class="interlanguage-link-target"><span>Ido</span></a></li><li class="interlanguage-link interwiki-id mw-list-item"><a href="https://id.wikipedia.org/wiki/Duolingo" title="Duolingo – Indonesian" lang="id" hreflang="id" data-title="Duolingo" data-language-autonym="Bahasa Indonesia" data-language-local-name="Indonesian" class="interlanguage-link-target"><span>Bahasa Indonesia</span></a></li><li class="interlanguage-link interwiki-ie mw-list-item"><a href="https://ie.wikipedia.org/wiki/Duolingo" title="Duolingo – Interlingue" lang="ie" hreflang="ie" data-title="Duolingo" data-language-autonym="Interlingue" data-language-local-name="Interlingue" class="interlanguage-link-target"><span>Interlingue</span></a></li><li class="interlanguage-link interwiki-it mw-list-item"><a href="https://it.wikipedia.org/wiki/Duolingo" title="Duolingo – Italian" lang="it" hreflang="it" data-title="Duolingo" data-language-autonym="Italiano" data-language-local-name="Italian" class="interlanguage-link-target"><span>Italiano</span></a></li><li class="interlanguage-link interwiki-he mw-list-item"><a href="https://he.wikipedia.org/wiki/%D7%93%D7%95%D7%90%D7%95%D7%9C%D7%99%D7%A0%D7%92%D7%95" title="דואולינגו – Hebrew" lang="he" hreflang="he" data-title="דואולינגו" data-language-autonym="עברית" data-language-local-name="Hebrew" class="interlanguage-link-target"><span>עברית</span></a></li><li class="interlanguage-link interwiki-jv mw-list-item"><a href="https://jv.wikipedia.org/wiki/Duolingo" title="Duolingo – Javanese" lang="jv" hreflang="jv" data-title="Duolingo" data-language-autonym="Jawa" data-language-local-name="Javanese" class="interlanguage-link-target"><span>Jawa</span></a></li><li class="interlanguage-link interwiki-ks mw-list-item"><a href="https://ks.wikipedia.org/wiki/%DA%88%D9%8F%D9%88%D9%8E%D9%84%D9%86%DA%AF%D9%88" title="ڈُوَلنگو – Kashmiri" lang="ks" hreflang="ks" data-title="ڈُوَلنگو" data-language-autonym="कॉशुर / کٲشُر" data-language-local-name="Kashmiri" class="interlanguage-link-target"><span>कॉशुर / کٲشُر</span></a></li><li class="interlanguage-link interwiki-kk mw-list-item"><a href="https://kk.wikipedia.org/wiki/Duolingo" title="Duolingo – Kazakh" lang="kk" hreflang="kk" data-title="Duolingo" data-language-autonym="Қазақша" data-language-local-name="Kazakh" class="interlanguage-link-target"><span>Қазақша</span></a></li><li class="interlanguage-link interwiki-sw mw-list-item"><a href="https://sw.wikipedia.org/wiki/Duolingo" title="Duolingo – Swahili" lang="sw" hreflang="sw" data-title="Duolingo" data-language-autonym="Kiswahili" data-language-local-name="Swahili" class="interlanguage-link-target"><span>Kiswahili</span></a></li><li class="interlanguage-link interwiki-lad mw-list-item"><a href="https://lad.wikipedia.org/wiki/Duolingo" title="Duolingo – Ladino" lang="lad" hreflang="lad" data-title="Duolingo" data-language-autonym="Ladino" data-language-local-name="Ladino" class="interlanguage-link-target"><span>Ladino</span></a></li><li class="interlanguage-link interwiki-lv mw-list-item"><a href="https://lv.wikipedia.org/wiki/Duolingo" title="Duolingo – Latvian" lang="lv" hreflang="lv" data-title="Duolingo" data-language-autonym="Latviešu" data-language-local-name="Latvian" class="interlanguage-link-target"><span>Latviešu</span></a></li><li class="interlanguage-link interwiki-lt mw-list-item"><a href="https://lt.wikipedia.org/wiki/Duolingo" title="Duolingo – Lithuanian" lang="lt" hreflang="lt" data-title="Duolingo" data-language-autonym="Lietuvių" data-language-local-name="Lithuanian" class="interlanguage-link-target"><span>Lietuvių</span></a></li><li class="interlanguage-link interwiki-hu mw-list-item"><a href="https://hu.wikipedia.org/wiki/Duolingo" title="Duolingo – Hungarian" lang="hu" hreflang="hu" data-title="Duolingo" data-language-autonym="Magyar" data-language-local-name="Hungarian" class="interlanguage-link-target"><span>Magyar</span></a></li><li class="interlanguage-link interwiki-ms mw-list-item"><a href="https://ms.wikipedia.org/wiki/Duolingo" title="Duolingo – Malay" lang="ms" hreflang="ms" data-title="Duolingo" data-language-autonym="Bahasa Melayu" data-language-local-name="Malay" class="interlanguage-link-target"><span>Bahasa Melayu</span></a></li><li class="interlanguage-link interwiki-my mw-list-item"><a href="https://my.wikipedia.org/wiki/%E1%80%92%E1%80%B1%E1%80%AB%E1%80%84%E1%80%BA%E1%80%9C%E1%80%84%E1%80%BA%E1%80%82%E1%80%AD%E1%80%AF" title="ဒေါင်လင်ဂို – Burmese" lang="my" hreflang="my" data-title="ဒေါင်လင်ဂို" data-language-autonym="မြန်မာဘာသာ" data-language-local-name="Burmese" class="interlanguage-link-target"><span>မြန်မာဘာသာ</span></a></li><li class="interlanguage-link interwiki-nl mw-list-item"><a href="https://nl.wikipedia.org/wiki/Duolingo" title="Duolingo – Dutch" lang="nl" hreflang="nl" data-title="Duolingo" data-language-autonym="Nederlands" data-language-local-name="Dutch" class="interlanguage-link-target"><span>Nederlands</span></a></li><li class="interlanguage-link interwiki-ja mw-list-item"><a href="https://ja.wikipedia.org/wiki/Duolingo" title="Duolingo – Japanese" lang="ja" hreflang="ja" data-title="Duolingo" data-language-autonym="日本語" data-language-local-name="Japanese" class="interlanguage-link-target"><span>日本語</span></a></li><li class="interlanguage-link interwiki-no mw-list-item"><a href="https://no.wikipedia.org/wiki/Duolingo" title="Duolingo – Norwegian Bokmål" lang="nb" hreflang="nb" data-title="Duolingo" data-language-autonym="Norsk bokmål" data-language-local-name="Norwegian Bokmål" class="interlanguage-link-target"><span>Norsk bokmål</span></a></li><li class="interlanguage-link interwiki-oc mw-list-item"><a href="https://oc.wikipedia.org/wiki/Duolingo" title="Duolingo – Occitan" lang="oc" hreflang="oc" data-title="Duolingo" data-language-autonym="Occitan" data-language-local-name="Occitan" class="interlanguage-link-target"><span>Occitan</span></a></li><li class="interlanguage-link interwiki-uz mw-list-item"><a href="https://uz.wikipedia.org/wiki/Duolingo" title="Duolingo – Uzbek" lang="uz" hreflang="uz" data-title="Duolingo" data-language-autonym="Oʻzbekcha / ўзбекча" data-language-local-name="Uzbek" class="interlanguage-link-target"><span>Oʻzbekcha / ўзбекча</span></a></li><li class="interlanguage-link interwiki-pa mw-list-item"><a href="https://pa.wikipedia.org/wiki/%E0%A8%A1%E0%A9%82%E0%A8%93%E0%A8%B2%E0%A8%BF%E0%A9%B0%E0%A8%97%E0%A9%8B" title="ਡੂਓਲਿੰਗੋ – Punjabi" lang="pa" hreflang="pa" data-title="ਡੂਓਲਿੰਗੋ" data-language-autonym="ਪੰਜਾਬੀ" data-language-local-name="Punjabi" class="interlanguage-link-target"><span>ਪੰਜਾਬੀ</span></a></li><li class="interlanguage-link interwiki-pnb mw-list-item"><a href="https://pnb.wikipedia.org/wiki/%DA%88%D9%88%D8%A4%D9%84%D9%86%DA%AF%D9%88" title="ڈوؤلنگو – Western Punjabi" lang="pnb" hreflang="pnb" data-title="ڈوؤلنگو" data-language-autonym="پنجابی" data-language-local-name="Western Punjabi" class="interlanguage-link-target"><span>پنجابی</span></a></li><li class="interlanguage-link interwiki-km mw-list-item"><a href="https://km.wikipedia.org/wiki/%E1%9E%8C%E1%9E%BC%E1%9E%9B%E1%9E%B8%E1%9E%84%E1%9E%A0%E1%9F%92%E1%9E%82%E1%9F%84" title="ឌូលីងហ្គោ – Khmer" lang="km" hreflang="km" data-title="ឌូលីងហ្គោ" data-language-autonym="ភាសាខ្មែរ" data-language-local-name="Khmer" class="interlanguage-link-target"><span>ភាសាខ្មែរ</span></a></li><li class="interlanguage-link interwiki-pl mw-list-item"><a href="https://pl.wikipedia.org/wiki/Duolingo" title="Duolingo – Polish" lang="pl" hreflang="pl" data-title="Duolingo" data-language-autonym="Polski" data-language-local-name="Polish" class="interlanguage-link-target"><span>Polski</span></a></li><li class="interlanguage-link interwiki-pt mw-list-item"><a href="https://pt.wikipedia.org/wiki/Duolingo" title="Duolingo – Portuguese" lang="pt" hreflang="pt" data-title="Duolingo" data-language-autonym="Português" data-language-local-name="Portuguese" class="interlanguage-link-target"><span>Português</span></a></li><li class="interlanguage-link interwiki-ro mw-list-item"><a href="https://ro.wikipedia.org/wiki/Duolingo" title="Duolingo – Romanian" lang="ro" hreflang="ro" data-title="Duolingo" data-language-autonym="Română" data-language-local-name="Romanian" class="interlanguage-link-target"><span>Română</span></a></li><li class="interlanguage-link interwiki-qu mw-list-item"><a href="https://qu.wikipedia.org/wiki/Duolingo" title="Duolingo – Quechua" lang="qu" hreflang="qu" data-title="Duolingo" data-language-autonym="Runa Simi" data-language-local-name="Quechua" class="interlanguage-link-target"><span>Runa Simi</span></a></li><li class="interlanguage-link interwiki-ru mw-list-item"><a href="https://ru.wikipedia.org/wiki/Duolingo" title="Duolingo – Russian" lang="ru" hreflang="ru" data-title="Duolingo" data-language-autonym="Русский" data-language-local-name="Russian" class="interlanguage-link-target"><span>Русский</span></a></li><li class="interlanguage-link interwiki-sah mw-list-item"><a href="https://sah.wikipedia.org/wiki/Duolingo" title="Duolingo – Yakut" lang="sah" hreflang="sah" data-title="Duolingo" data-language-autonym="Саха тыла" data-language-local-name="Yakut" class="interlanguage-link-target"><span>Саха тыла</span></a></li><li class="interlanguage-link interwiki-sco mw-list-item"><a href="https://sco.wikipedia.org/wiki/Duolingo" title="Duolingo – Scots" lang="sco" hreflang="sco" data-title="Duolingo" data-language-autonym="Scots" data-language-local-name="Scots" class="interlanguage-link-target"><span>Scots</span></a></li><li class="interlanguage-link interwiki-simple mw-list-item"><a href="https://simple.wikipedia.org/wiki/Duolingo" title="Duolingo – Simple English" lang="en-simple" hreflang="en-simple" data-title="Duolingo" data-language-autonym="Simple English" data-language-local-name="Simple English" class="interlanguage-link-target"><span>Simple English</span></a></li><li class="interlanguage-link interwiki-sk mw-list-item"><a href="https://sk.wikipedia.org/wiki/Duolingo" title="Duolingo – Slovak" lang="sk" hreflang="sk" data-title="Duolingo" data-language-autonym="Slovenčina" data-language-local-name="Slovak" class="interlanguage-link-target"><span>Slovenčina</span></a></li><li class="interlanguage-link interwiki-ckb mw-list-item"><a href="https://ckb.wikipedia.org/wiki/%D8%AF%DB%86%D9%84%DB%8C%D9%86%DA%AF%DB%86" title="دۆلینگۆ – Central Kurdish" lang="ckb" hreflang="ckb" data-title="دۆلینگۆ" data-language-autonym="کوردی" data-language-local-name="Central Kurdish" class="interlanguage-link-target"><span>کوردی</span></a></li><li class="interlanguage-link interwiki-sr mw-list-item"><a href="https://sr.wikipedia.org/wiki/%D0%94%D1%83%D0%BE%D0%BB%D0%B8%D0%BD%D0%B3%D0%BE" title="Дуолинго – Serbian" lang="sr" hreflang="sr" data-title="Дуолинго" data-language-autonym="Српски / srpski" data-language-local-name="Serbian" class="interlanguage-link-target"><span>Српски / srpski</span></a></li><li class="interlanguage-link interwiki-fi mw-list-item"><a href="https://fi.wikipedia.org/wiki/Duolingo" title="Duolingo – Finnish" lang="fi" hreflang="fi" data-title="Duolingo" data-language-autonym="Suomi" data-language-local-name="Finnish" class="interlanguage-link-target"><span>Suomi</span></a></li><li class="interlanguage-link interwiki-sv mw-list-item"><a href="https://sv.wikipedia.org/wiki/Duolingo" title="Duolingo – Swedish" lang="sv" hreflang="sv" data-title="Duolingo" data-language-autonym="Svenska" data-language-local-name="Swedish" class="interlanguage-link-target"><span>Svenska</span></a></li><li class="interlanguage-link interwiki-tl mw-list-item"><a href="https://tl.wikipedia.org/wiki/Duolingo" title="Duolingo – Tagalog" lang="tl" hreflang="tl" data-title="Duolingo" data-language-autonym="Tagalog" data-language-local-name="Tagalog" class="interlanguage-link-target"><span>Tagalog</span></a></li><li class="interlanguage-link interwiki-ta mw-list-item"><a href="https://ta.wikipedia.org/wiki/%E0%AE%9F%E0%AF%81%E0%AE%B5%E0%AF%8B%E0%AE%B2%E0%AE%BF%E0%AE%99%E0%AF%8D%E0%AE%95%E0%AF%8B" title="டுவோலிங்கோ – Tamil" lang="ta" hreflang="ta" data-title="டுவோலிங்கோ" data-language-autonym="தமிழ்" data-language-local-name="Tamil" class="interlanguage-link-target"><span>தமிழ்</span></a></li><li class="interlanguage-link interwiki-th mw-list-item"><a href="https://th.wikipedia.org/wiki/%E0%B8%94%E0%B8%B4%E0%B8%A7%E0%B9%82%E0%B8%AD%E0%B8%A5%E0%B8%B4%E0%B8%87%E0%B9%82%E0%B8%81" title="ดิวโอลิงโก – Thai" lang="th" hreflang="th" data-title="ดิวโอลิงโก" data-language-autonym="ไทย" data-language-local-name="Thai" class="interlanguage-link-target"><span>ไทย</span></a></li><li class="interlanguage-link interwiki-tr mw-list-item"><a href="https://tr.wikipedia.org/wiki/Duolingo" title="Duolingo – Turkish" lang="tr" hreflang="tr" data-title="Duolingo" data-language-autonym="Türkçe" data-language-local-name="Turkish" class="interlanguage-link-target"><span>Türkçe</span></a></li><li class="interlanguage-link interwiki-uk mw-list-item"><a href="https://uk.wikipedia.org/wiki/Duolingo" title="Duolingo – Ukrainian" lang="uk" hreflang="uk" data-title="Duolingo" data-language-autonym="Українська" data-language-local-name="Ukrainian" class="interlanguage-link-target"><span>Українська</span></a></li><li class="interlanguage-link interwiki-ur mw-list-item"><a href="https://ur.wikipedia.org/wiki/%DA%88%D8%A4%D9%84%D9%86%DA%AF%D9%88" title="ڈؤلنگو – Urdu" lang="ur" hreflang="ur" data-title="ڈؤلنگو" data-language-autonym="اردو" data-language-local-name="Urdu" class="interlanguage-link-target"><span>اردو</span></a></li><li class="interlanguage-link interwiki-vi mw-list-item"><a href="https://vi.wikipedia.org/wiki/Duolingo" title="Duolingo – Vietnamese" lang="vi" hreflang="vi" data-title="Duolingo" data-language-autonym="Tiếng Việt" data-language-local-name="Vietnamese" class="interlanguage-link-target"><span>Tiếng Việt</span></a></li><li class="interlanguage-link interwiki-wa mw-list-item"><a href="https://wa.wikipedia.org/wiki/Duolingo" title="Duolingo – Walloon" lang="wa" hreflang="wa" data-title="Duolingo" data-language-autonym="Walon" data-language-local-name="Walloon" class="interlanguage-link-target"><span>Walon</span></a></li><li class="interlanguage-link interwiki-zh-classical mw-list-item"><a href="https://zh-classical.wikipedia.org/wiki/%E5%A4%9A%E9%84%B0%E5%9C%8B" title="多鄰國 – Literary Chinese" lang="lzh" hreflang="lzh" data-title="多鄰國" data-language-autonym="文言" data-language-local-name="Literary Chinese" class="interlanguage-link-target"><span>文言</span></a></li><li class="interlanguage-link interwiki-vls mw-list-item"><a href="https://vls.wikipedia.org/wiki/Duolingo" title="Duolingo – West Flemish" lang="vls" hreflang="vls" data-title="Duolingo" data-language-autonym="West-Vlams" data-language-local-name="West Flemish" class="interlanguage-link-target"><span>West-Vlams</span></a></li><li class="interlanguage-link interwiki-wuu mw-list-item"><a href="https://wuu.wikipedia.org/wiki/%E5%A4%9A%E9%82%BB%E5%9B%BD" title="多邻国 – Wu" lang="wuu" hreflang="wuu" data-title="多邻国" data-language-autonym="吴语" data-language-local-name="Wu" class="interlanguage-link-target"><span>吴语</span></a></li><li class="interlanguage-link interwiki-yi mw-list-item"><a href="https://yi.wikipedia.org/wiki/%D7%93%D7%95%D7%9C%D7%99%D7%A0%D7%92%D7%95" title="דולינגו – Yiddish" lang="yi" hreflang="yi" data-title="דולינגו" data-language-autonym="ייִדיש" data-language-local-name="Yiddish" class="interlanguage-link-target"><span>ייִדיש</span></a></li><li class="interlanguage-link interwiki-zh-yue mw-list-item"><a href="https://zh-yue.wikipedia.org/wiki/Duolingo" title="Duolingo – Cantonese" lang="yue" hreflang="yue" data-title="Duolingo" data-language-autonym="粵語" data-language-local-name="Cantonese" class="interlanguage-link-target"><span>粵語</span></a></li><li class="interlanguage-link interwiki-bat-smg mw-list-item"><a href="https://bat-smg.wikipedia.org/wiki/Duolingo" title="Duolingo – Samogitian" lang="sgs" hreflang="sgs" data-title="Duolingo" data-language-autonym="Žemaitėška" data-language-local-name="Samogitian" class="interlanguage-link-target"><span>Žemaitėška</span></a></li><li class="interlanguage-link interwiki-zh mw-list-item"><a href="https://zh.wikipedia.org/wiki/%E5%A4%9A%E9%84%B0%E5%9C%8B" title="多鄰國 – Chinese" lang="zh" hreflang="zh" data-title="多鄰國" data-language-autonym="中文" data-language-local-name="Chinese" class="interlanguage-link-target"><span>中文</span></a></li><li class="interlanguage-link interwiki-zgh mw-list-item"><a href="https://zgh.wikipedia.org/wiki/%E2%B4%B7%E2%B5%93%E2%B5%8D%E2%B5%89%E2%B5%8F%E2%B4%B3%E2%B5%93" title="ⴷⵓⵍⵉⵏⴳⵓ – Standard Moroccan Tamazight" lang="zgh" hreflang="zgh" data-title="ⴷⵓⵍⵉⵏⴳⵓ" data-language-autonym="ⵜⴰⵎⴰⵣⵉⵖⵜ ⵜⴰⵏⴰⵡⴰⵢⵜ" data-language-local-name="Standard Moroccan Tamazight" class="interlanguage-link-target"><span>ⵜⴰⵎⴰⵣⵉⵖⵜ ⵜⴰⵏⴰⵡⴰⵢⵜ</span></a></li> </ul> <div class="after-portlet after-portlet-lang"><span class="wb-langlinks-edit wb-langlinks-link"><a href="https://www.wikidata.org/wiki/Special:EntityPage/Q2918660#sitelinks-wikipedia" title="Edit interlanguage links" class="wbc-editpage">Edit links</a></span></div> </div> </div> </div> </header> <div class="vector-page-toolbar"> <div class="vector-page-toolbar-container"> <div id="left-navigation"> <nav aria-label="Namespaces"> <div id="p-associated-pages" class="vector-menu vector-menu-tabs mw-portlet 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.mw-parser-output .infobox-full-data:not(.notheme)>div:not(.notheme)[style]{background:#1f1f23!important;color:#f8f9fa}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .infobox-full-data:not(.notheme) div:not(.notheme){background:#1f1f23!important;color:#f8f9fa}}@media(min-width:640px){body.skin--responsive .mw-parser-output .infobox-table{display:table!important}body.skin--responsive .mw-parser-output .infobox-table>caption{display:table-caption!important}body.skin--responsive .mw-parser-output .infobox-table>tbody{display:table-row-group}body.skin--responsive .mw-parser-output .infobox-table tr{display:table-row!important}body.skin--responsive .mw-parser-output .infobox-table th,body.skin--responsive .mw-parser-output .infobox-table td{padding-left:inherit;padding-right:inherit}}</style><table class="infobox vcard"><caption class="infobox-title fn org">Duolingo, Inc.</caption><tbody><tr><td colspan="2" class="infobox-image"><span class="mw-default-size" typeof="mw:File/Frameless"><a href="/wiki/File:Duolingo_logo_(2019).svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/5/5c/Duolingo_logo_%282019%29.svg/220px-Duolingo_logo_%282019%29.svg.png" decoding="async" width="220" height="51" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/5/5c/Duolingo_logo_%282019%29.svg/330px-Duolingo_logo_%282019%29.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/5/5c/Duolingo_logo_%282019%29.svg/440px-Duolingo_logo_%282019%29.svg.png 2x" data-file-width="1000" data-file-height="234" /></a></span></td></tr><tr><td colspan="2" class="infobox-image"><span typeof="mw:File"><a href="/wiki/File:Duolingo_home_page.png" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/en/thumb/5/59/Duolingo_home_page.png/300px-Duolingo_home_page.png" decoding="async" width="300" height="147" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/5/59/Duolingo_home_page.png/450px-Duolingo_home_page.png 1.5x, //upload.wikimedia.org/wikipedia/en/5/59/Duolingo_home_page.png 2x" data-file-width="451" data-file-height="221" /></a></span><div class="infobox-caption">Duolingo <a href="/wiki/Home_page" title="Home page">home page</a> visited while logged out in March 2024</div></td></tr><tr><th scope="row" class="infobox-label">Type of business</th><td class="infobox-data category"><a href="/wiki/Public_company" title="Public company">Public</a></td></tr><tr><th scope="row" class="infobox-label">Available&#160;in</th><td class="infobox-data"><div class="collapsible-list mw-collapsible mw-collapsed" style="text-align: left;"> <div style="line-height: 1.6em; font-weight: bold;"><div>Multilingual</div></div> <ul class="mw-collapsible-content" style="margin-top: 0; margin-bottom: 0; line-height: inherit; list-style: none; margin-left: 0;"><li style="line-height: inherit; margin: 0"><a href="/wiki/Arabic_language" class="mw-redirect" title="Arabic language">Arabic</a> </li><li style="line-height: inherit; margin: 0"><a href="/wiki/Bengali_language" title="Bengali language">Bengali</a> </li><li style="line-height: inherit; margin: 0"><a href="/wiki/Chinese_language" title="Chinese language">Chinese</a> </li><li style="line-height: inherit; margin: 0"><a href="/wiki/Czech_language" title="Czech language">Czech</a> </li><li style="line-height: inherit; margin: 0"><a href="/wiki/Dutch_language" title="Dutch language">Dutch</a> </li><li style="line-height: inherit; margin: 0"><a href="/wiki/English_language" title="English language">English</a> </li><li style="line-height: inherit; margin: 0"><a href="/wiki/French_language" title="French language">French</a> </li><li style="line-height: inherit; margin: 0"><a href="/wiki/German_language" title="German language">German</a> </li><li style="line-height: inherit; margin: 0"><a href="/wiki/Greek_language" title="Greek language">Greek</a> </li><li style="line-height: inherit; margin: 0"><a href="/wiki/Hindi" title="Hindi">Hindi</a> </li><li style="line-height: inherit; margin: 0"><a href="/wiki/Hungarian_language" title="Hungarian language">Hungarian</a> </li><li style="line-height: inherit; margin: 0"><a href="/wiki/Indonesian_language" title="Indonesian language">Indonesian</a> </li><li style="line-height: inherit; margin: 0"><a href="/wiki/Italian_language" title="Italian language">Italian</a> </li><li style="line-height: inherit; margin: 0"><a href="/wiki/Japanese_language" title="Japanese language">Japanese</a> </li><li style="line-height: inherit; margin: 0"><a href="/wiki/Korean_language" title="Korean language">Korean</a> </li><li style="line-height: inherit; margin: 0"><a href="/wiki/Polish_language" title="Polish language">Polish</a> </li><li style="line-height: inherit; margin: 0"><a href="/wiki/Portuguese_language" title="Portuguese language">Portuguese</a> </li><li style="line-height: inherit; margin: 0"><a href="/wiki/Romanian_language" title="Romanian language">Romanian</a> </li><li style="line-height: inherit; margin: 0"><a href="/wiki/Russian_language" title="Russian language">Russian</a> </li><li style="line-height: inherit; margin: 0"><a href="/wiki/Spanish_language" title="Spanish language">Spanish</a> </li><li style="line-height: inherit; margin: 0"><a href="/wiki/Swedish_language" title="Swedish language">Swedish</a> </li><li style="line-height: inherit; margin: 0"><a href="/wiki/Tagalog_language" title="Tagalog language">Tagalog</a> </li><li style="line-height: inherit; margin: 0"><a href="/wiki/Telugu_language" title="Telugu language">Telugu</a> </li><li style="line-height: inherit; margin: 0"><a href="/wiki/Thai_language" title="Thai language">Thai</a> </li><li style="line-height: inherit; margin: 0"><a href="/wiki/Turkish_language" title="Turkish language">Turkish</a> </li><li style="line-height: inherit; margin: 0"><a href="/wiki/Ukrainian_language" title="Ukrainian language">Ukrainian</a> </li><li style="line-height: inherit; margin: 0"><a href="/wiki/Vietnamese_language" title="Vietnamese language">Vietnamese</a> </li></ul> </div></td></tr><tr><th scope="row" class="infobox-label"><a href="/wiki/Ticker_symbol" title="Ticker symbol">Traded&#160;as</a></th><td class="infobox-data"><style data-mw-deduplicate="TemplateStyles:r1126788409">.mw-parser-output .plainlist ol,.mw-parser-output .plainlist ul{line-height:inherit;list-style:none;margin:0;padding:0}.mw-parser-output .plainlist ol li,.mw-parser-output .plainlist ul li{margin-bottom:0}</style><div class="plainlist"><ul><li><a href="/wiki/Nasdaq" title="Nasdaq">Nasdaq</a>:&#160;<a rel="nofollow" class="external text" href="https://www.nasdaq.com/market-activity/stocks/duol">DUOL</a> (Class A)</li><li><a href="/wiki/S%26P_400" title="S&amp;P 400">S&amp;P 400</a> component</li></ul></div></td></tr><tr><th scope="row" class="infobox-label">Founded</th><td class="infobox-data">2011<span class="noprint">&#59;&#32;13&#160;years ago</span><span style="display:none">&#160;(<span class="bday dtstart published updated">2011</span>)</span></td></tr><tr><th scope="row" class="infobox-label">Headquarters</th><td class="infobox-data label"><a href="/wiki/Pittsburgh,_Pennsylvania" class="mw-redirect" title="Pittsburgh, Pennsylvania">Pittsburgh, Pennsylvania</a>, U.S.</td></tr><tr><th scope="row" class="infobox-label">Area&#160;served</th><td class="infobox-data">Worldwide</td></tr><tr><th scope="row" class="infobox-label"><a href="/wiki/Organizational_founder" title="Organizational founder">Founder(s)</a></th><td class="infobox-data"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1126788409"><div class="plainlist"><ul><li><a href="/wiki/Luis_von_Ahn" title="Luis von Ahn">Luis von Ahn</a></li><li><a href="/wiki/Severin_Hacker" title="Severin Hacker">Severin Hacker</a></li></ul></div></td></tr><tr><th scope="row" class="infobox-label">Key&#160;people</th><td class="infobox-data">Luis von Ahn (<a href="/wiki/CEO" class="mw-redirect" title="CEO">CEO</a>)<br />Severin Hacker (<a href="/wiki/Chief_technology_officer" title="Chief technology officer">CTO</a>)</td></tr><tr><th scope="row" class="infobox-label">Industry</th><td class="infobox-data category"><a href="/wiki/Online_education" class="mw-redirect" title="Online education">Online education</a></td></tr><tr><th scope="row" class="infobox-label"><a href="/wiki/Product_(business)" title="Product (business)">Products</a></th><td class="infobox-data"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1126788409"><div class="plainlist"> <ul><li>Duolingo</li> <li>Duolingo ABC</li> <li><a href="/wiki/Duolingo_English_Test" title="Duolingo English Test">Duolingo English Test</a></li></ul> </div></td></tr><tr><th scope="row" class="infobox-label"><a href="/wiki/Service_(economics)" title="Service (economics)">Services</a></th><td class="infobox-data">Language, music, and mathematics courses and language assessment.</td></tr><tr><th scope="row" class="infobox-label"><a href="/wiki/Revenue" title="Revenue">Revenue</a></th><td class="infobox-data"><span typeof="mw:File"><span title="Increase"><img alt="Increase" src="//upload.wikimedia.org/wikipedia/commons/thumb/b/b0/Increase2.svg/11px-Increase2.svg.png" decoding="async" width="11" height="11" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/b/b0/Increase2.svg/17px-Increase2.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/b/b0/Increase2.svg/22px-Increase2.svg.png 2x" data-file-width="300" data-file-height="300" /></span></span> <span style="white-space: nowrap"><a href="/wiki/United_States_dollar" title="United States dollar">US$</a>531 million</span> (2023)</td></tr><tr><th scope="row" class="infobox-label"><a href="/wiki/Earnings_before_interest_and_taxes" title="Earnings before interest and taxes">Operating income</a></th><td class="infobox-data"><span typeof="mw:File"><span title="Negative increase"><img alt="Negative increase" src="//upload.wikimedia.org/wikipedia/commons/thumb/5/59/Increase_Negative.svg/11px-Increase_Negative.svg.png" decoding="async" width="11" height="11" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/5/59/Increase_Negative.svg/17px-Increase_Negative.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/5/59/Increase_Negative.svg/22px-Increase_Negative.svg.png 2x" data-file-width="300" data-file-height="300" /></span></span> <span style="white-space: nowrap">US$−13 million</span> (2023)</td></tr><tr><th scope="row" class="infobox-label"><a href="/wiki/Net_income" title="Net income">Profit</a></th><td class="infobox-data"><span typeof="mw:File"><span title="Increase"><img alt="Increase" src="//upload.wikimedia.org/wikipedia/commons/thumb/b/b0/Increase2.svg/11px-Increase2.svg.png" decoding="async" width="11" height="11" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/b/b0/Increase2.svg/17px-Increase2.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/b/b0/Increase2.svg/22px-Increase2.svg.png 2x" data-file-width="300" data-file-height="300" /></span></span> <span style="white-space: nowrap">US$16.1 million</span> (2023)</td></tr><tr><th scope="row" class="infobox-label"><a href="/wiki/Asset" title="Asset">Total assets</a></th><td class="infobox-data"><span typeof="mw:File"><span title="Increase"><img alt="Increase" src="//upload.wikimedia.org/wikipedia/commons/thumb/b/b0/Increase2.svg/11px-Increase2.svg.png" decoding="async" width="11" height="11" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/b/b0/Increase2.svg/17px-Increase2.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/b/b0/Increase2.svg/22px-Increase2.svg.png 2x" data-file-width="300" data-file-height="300" /></span></span> <span style="white-space: nowrap">US$954 million</span> (2023)</td></tr><tr><th scope="row" class="infobox-label"><a href="/wiki/Equity_(finance)" title="Equity (finance)">Total equity</a></th><td class="infobox-data"><span typeof="mw:File"><span title="Increase"><img alt="Increase" src="//upload.wikimedia.org/wikipedia/commons/thumb/b/b0/Increase2.svg/11px-Increase2.svg.png" decoding="async" width="11" height="11" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/b/b0/Increase2.svg/17px-Increase2.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/b/b0/Increase2.svg/22px-Increase2.svg.png 2x" data-file-width="300" data-file-height="300" /></span></span> <span style="white-space: nowrap">US$656 million</span> (2023)</td></tr><tr><th scope="row" class="infobox-label">Employees</th><td class="infobox-data">≈&#160;850 (September 2024)</td></tr><tr><th scope="row" class="infobox-label">URL</th><td class="infobox-data url"><span class="url"><a rel="nofollow" class="external text" href="http://duolingo.com">duolingo<wbr />.com</a></span></td></tr><tr><th scope="row" class="infobox-label"><a href="/wiki/Online_advertising" title="Online advertising">Advertising</a></th><td class="infobox-data">Yes</td></tr><tr><th scope="row" class="infobox-label">Registration</th><td class="infobox-data">Yes<sup id="cite_ref-Registration_1-0" class="reference"><a href="#cite_note-Registration-1"><span class="cite-bracket">&#91;</span>a<span class="cite-bracket">&#93;</span></a></sup></td></tr><tr><th scope="row" class="infobox-label"><a href="/wiki/Registered_user" title="Registered user">Users</a></th><td class="infobox-data">113 million <a href="/wiki/Monthly_active_users" class="mw-redirect" title="Monthly active users">MAU</a> (Q3 2024)</td></tr><tr><th scope="row" class="infobox-label">Launched</th><td class="infobox-data">November&#160;27, 2011<span class="noprint">&#59;&#32;12 years ago</span><span style="display:none">&#160;(<span class="bday dtstart published updated">2011-11-27</span>)</span> (private beta)<br />June&#160;19, 2012<span class="noprint">&#59;&#32;12 years ago</span><span style="display:none">&#160;(<span class="bday dtstart published updated">2012-06-19</span>)</span> (public release)</td></tr><tr><th scope="row" class="infobox-label">Current&#160;status</th><td class="infobox-data category">Online</td></tr><tr><th scope="row" class="infobox-label"><a href="/wiki/Computing_platform" title="Computing platform">Native client(s) on</a></th><td class="infobox-data"><a href="/wiki/Android_(operating_system)" title="Android (operating system)">Android</a>, <a href="/wiki/IOS" title="IOS">iOS</a>, <a href="/wiki/IPadOS" title="IPadOS">iPadOS</a></td></tr><tr><td colspan="2" class="infobox-below"><sup id="cite_ref-10K_2-0" class="reference"><a href="#cite_note-10K-2"><span class="cite-bracket">&#91;</span>1<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-kotlin_3-0" class="reference"><a href="#cite_note-kotlin-3"><span class="cite-bracket">&#91;</span>2<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-real_world_swift_4-0" class="reference"><a href="#cite_note-real_world_swift-4"><span class="cite-bracket">&#91;</span>3<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-making.duolingo.com_5-0" class="reference"><a href="#cite_note-making.duolingo.com-5"><span class="cite-bracket">&#91;</span>4<span class="cite-bracket">&#93;</span></a></sup></td></tr></tbody></table> <p><b>Duolingo, Inc.</b>,<sup id="cite_ref-6" class="reference"><a href="#cite_note-6"><span class="cite-bracket">&#91;</span>b<span class="cite-bracket">&#93;</span></a></sup> is an American <a href="/wiki/Educational_technology" title="Educational technology">educational technology</a> company that produces learning <a href="/wiki/Mobile_app" title="Mobile app">apps</a> and provides <a href="/wiki/Language_assessment" title="Language assessment">language certification</a>. Duolingo offers courses on music,<sup id="cite_ref-7" class="reference"><a href="#cite_note-7"><span class="cite-bracket">&#91;</span>5<span class="cite-bracket">&#93;</span></a></sup> math,<sup id="cite_ref-math_8-0" class="reference"><a href="#cite_note-math-8"><span class="cite-bracket">&#91;</span>6<span class="cite-bracket">&#93;</span></a></sup> and 43 languages,<sup id="cite_ref-:3_9-0" class="reference"><a href="#cite_note-:3-9"><span class="cite-bracket">&#91;</span>7<span class="cite-bracket">&#93;</span></a></sup> ranging from <a href="/wiki/English_language" title="English language">English</a>, <a href="/wiki/French_language" title="French language">French</a>, and <a href="/wiki/Spanish_language" title="Spanish language">Spanish</a> to less commonly studied languages such as <a href="/wiki/Welsh_language" title="Welsh language">Welsh</a>, <a href="/wiki/Irish_language" title="Irish language">Irish</a>, and <a href="/wiki/Navajo_language" title="Navajo language">Navajo</a>, and even fictional languages such as <a href="/wiki/Klingon_language" title="Klingon language">Klingon</a>.<sup id="cite_ref-10" class="reference"><a href="#cite_note-10"><span class="cite-bracket">&#91;</span>8<span class="cite-bracket">&#93;</span></a></sup> The learning method incorporates <a href="/wiki/Gamification_of_learning" title="Gamification of learning">gamification</a> to motivate users with points and rewards and interactive lessons featuring <a href="/wiki/Spaced_repetition" title="Spaced repetition">spaced repetition</a>.<sup id="cite_ref-11" class="reference"><a href="#cite_note-11"><span class="cite-bracket">&#91;</span>9<span class="cite-bracket">&#93;</span></a></sup> The app promotes short, daily lessons for consistent-phased practice. </p><p>Duolingo also offers the <a href="/wiki/Duolingo_English_Test" title="Duolingo English Test">Duolingo English Test</a>, an online <a href="/wiki/Language_assessment" title="Language assessment">language assessment</a>, and Duolingo ABC, a literacy app designed for children. The company follows a <a href="/wiki/Freemium" title="Freemium">freemium</a> model, with optional premium services like Super Duolingo and Duolingo Max, which are ad-free and provide additional features. Additionally, Duolingo runs <a href="#Duo&#39;s_Taqueria">Duo's Taqueria</a>, a Mexican taco restaurant. </p><p>With over 100 million monthly active users, Duolingo is the most popular language learning app.<sup id="cite_ref-12" class="reference"><a href="#cite_note-12"><span class="cite-bracket">&#91;</span>10<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-13" class="reference"><a href="#cite_note-13"><span class="cite-bracket">&#91;</span>11<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-14" class="reference"><a href="#cite_note-14"><span class="cite-bracket">&#91;</span>12<span class="cite-bracket">&#93;</span></a></sup> Learners on Duolingo complete more than 13 billion exercises per week.<sup id="cite_ref-15" class="reference"><a href="#cite_note-15"><span class="cite-bracket">&#91;</span>13<span class="cite-bracket">&#93;</span></a></sup> A <a href="/wiki/Systematic_review" title="Systematic review">systematic review</a> of <a href="/wiki/Scientific_literature" title="Scientific literature">research</a> on Duolingo from 2012 to 2020 found comparatively few studies on the platform's efficiency for <a href="/wiki/Language_acquisition" title="Language acquisition">language learning</a> but identified several studies that reported relatively high user satisfaction, enjoyment, and positive perceptions of the app's effectiveness.<sup id="cite_ref-16" class="reference"><a href="#cite_note-16"><span class="cite-bracket">&#91;</span>14<span class="cite-bracket">&#93;</span></a></sup> The company has also been recognized for its successful marketing tactics and strong <a href="/wiki/Brand_engagement" title="Brand engagement">brand engagement</a>.<sup id="cite_ref-17" class="reference"><a href="#cite_note-17"><span class="cite-bracket">&#91;</span>15<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-18" class="reference"><a href="#cite_note-18"><span class="cite-bracket">&#91;</span>16<span class="cite-bracket">&#93;</span></a></sup> </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="History">History</h2></div> <div class="mw-heading mw-heading3"><h3 id="Early_history">Early history</h3></div> <p>The idea for Duolingo was formulated in 2009 by <a href="/wiki/Carnegie_Mellon_University" title="Carnegie Mellon University">Carnegie Mellon University</a> professor <a href="/wiki/Luis_von_Ahn" title="Luis von Ahn">Luis von Ahn</a> and his Swiss-born post-graduate student <a href="/wiki/Severin_Hacker" title="Severin Hacker">Severin Hacker</a>.<sup id="cite_ref-TechCrunch_Article_19-0" class="reference"><a href="#cite_note-TechCrunch_Article-19"><span class="cite-bracket">&#91;</span>17<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-vator.tv_20-0" class="reference"><a href="#cite_note-vator.tv-20"><span class="cite-bracket">&#91;</span>18<span class="cite-bracket">&#93;</span></a></sup> Von Ahn had sold his second company, <a href="/wiki/ReCAPTCHA" title="ReCAPTCHA">reCAPTCHA</a>, to <a href="/wiki/Google" title="Google">Google</a> and, with Hacker, wanted to work on an education-related project.<sup id="cite_ref-21" class="reference"><a href="#cite_note-21"><span class="cite-bracket">&#91;</span>19<span class="cite-bracket">&#93;</span></a></sup> Von Ahn stated that he saw how expensive it was for people in his community in <a href="/wiki/Guatemala" title="Guatemala">Guatemala</a> to learn English.<sup id="cite_ref-Businessweek_2022_22-0" class="reference"><a href="#cite_note-Businessweek_2022-22"><span class="cite-bracket">&#91;</span>20<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-lifestyle.livemint.com_23-0" class="reference"><a href="#cite_note-lifestyle.livemint.com-23"><span class="cite-bracket">&#91;</span>21<span class="cite-bracket">&#93;</span></a></sup> Hacker (co-founder and current <a href="/wiki/Chief_technology_officer" title="Chief technology officer">CTO</a> of Duolingo) believed that "free education will really change the world"<sup id="cite_ref-:0_24-0" class="reference"><a href="#cite_note-:0-24"><span class="cite-bracket">&#91;</span>22<span class="cite-bracket">&#93;</span></a></sup> and wanted to provide an accessible means for doing so. He was recognized by the <a href="/wiki/National_Inventors_Hall_of_Fame" title="National Inventors Hall of Fame">National Inventors Hall of Fame</a> for his contributions to language learning and technological development.<sup id="cite_ref-25" class="reference"><a href="#cite_note-25"><span class="cite-bracket">&#91;</span>23<span class="cite-bracket">&#93;</span></a></sup> The Duo mascot is a green owl because co-founder Severin Hacker hates the color green.<sup id="cite_ref-26" class="reference"><a href="#cite_note-26"><span class="cite-bracket">&#91;</span>24<span class="cite-bracket">&#93;</span></a></sup> </p><p>The project was originally financed by von Ahn's <a href="/wiki/MacArthur_fellowship" class="mw-redirect" title="MacArthur fellowship">MacArthur fellowship</a> and a <a href="/wiki/National_Science_Foundation" title="National Science Foundation">National Science Foundation</a> grant.<sup id="cite_ref-NSFGrant_27-0" class="reference"><a href="#cite_note-NSFGrant-27"><span class="cite-bracket">&#91;</span>25<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-28" class="reference"><a href="#cite_note-28"><span class="cite-bracket">&#91;</span>26<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-NewScientist_29-0" class="reference"><a href="#cite_note-NewScientist-29"><span class="cite-bracket">&#91;</span>27<span class="cite-bracket">&#93;</span></a></sup> The founders considered creating Duolingo as a <a href="/wiki/Nonprofit_organization" title="Nonprofit organization">nonprofit organization</a>, but Von Ahn judged this model unsustainable.<sup id="cite_ref-:0_24-1" class="reference"><a href="#cite_note-:0-24"><span class="cite-bracket">&#91;</span>22<span class="cite-bracket">&#93;</span></a></sup> Its early revenue stream, a <a href="/wiki/Crowdsourced" class="mw-redirect" title="Crowdsourced">crowdsourced</a> translation service, was replaced by a <a href="/wiki/Duolingo_English_Test" title="Duolingo English Test">Duolingo English Test</a> certification program, advertising, and subscription.<sup id="cite_ref-:1_30-0" class="reference"><a href="#cite_note-:1-30"><span class="cite-bracket">&#91;</span>28<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-31" class="reference"><a href="#cite_note-31"><span class="cite-bracket">&#91;</span>29<span class="cite-bracket">&#93;</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Funds">Funds</h3></div> <figure class="mw-default-size mw-halign-left" typeof="mw:File/Thumb"><a href="/wiki/File:Duolingo_logo.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/1/15/Duolingo_logo.svg/220px-Duolingo_logo.svg.png" decoding="async" width="220" height="56" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/1/15/Duolingo_logo.svg/330px-Duolingo_logo.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/1/15/Duolingo_logo.svg/440px-Duolingo_logo.svg.png 2x" data-file-width="275" data-file-height="70" /></a><figcaption>Duolingo logo from 2011 to 2019</figcaption></figure> <p>In October 2011, Duolingo announced that it had raised $3.3&#160;million from a <a href="/wiki/Series_A_round" title="Series A round">Series&#160;A&#160;round</a> of funding, led by <a href="/wiki/Union_Square_Ventures" title="Union Square Ventures">Union Square Ventures</a>, with participation from author <a href="/wiki/Tim_Ferriss" title="Tim Ferriss">Tim Ferriss</a> and actor <a href="/wiki/Ashton_Kutcher" title="Ashton Kutcher">Ashton Kutcher</a>'s investing firm <a href="/wiki/A-Grade_Investments" title="A-Grade Investments">A-Grade Investments</a>.<sup id="cite_ref-wsj_32-0" class="reference"><a href="#cite_note-wsj-32"><span class="cite-bracket">&#91;</span>30<span class="cite-bracket">&#93;</span></a></sup> Duolingo launched a private beta on November 27, 2011, and accumulated a waiting list of more than 300,000 people.<sup id="cite_ref-vator.tv_20-1" class="reference"><a href="#cite_note-vator.tv-20"><span class="cite-bracket">&#91;</span>18<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-33" class="reference"><a href="#cite_note-33"><span class="cite-bracket">&#91;</span>31<span class="cite-bracket">&#93;</span></a></sup> It launched to the general public on June 19, 2012, at which point the waiting list had grown to around 500,000.<sup id="cite_ref-34" class="reference"><a href="#cite_note-34"><span class="cite-bracket">&#91;</span>32<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-35" class="reference"><a href="#cite_note-35"><span class="cite-bracket">&#91;</span>33<span class="cite-bracket">&#93;</span></a></sup> </p><p>In September 2012, Duolingo announced that it had raised a further $15&#160;million from a Series B funding round led by <a href="/wiki/New_Enterprise_Associates" title="New Enterprise Associates">New Enterprise Associates</a>, with participation from Union Square Ventures.<sup id="cite_ref-36" class="reference"><a href="#cite_note-36"><span class="cite-bracket">&#91;</span>34<span class="cite-bracket">&#93;</span></a></sup> In November 2012, Duolingo released an <a href="/wiki/IPhone" title="IPhone">iPhone</a> app,<sup id="cite_ref-TCiOS_37-0" class="reference"><a href="#cite_note-TCiOS-37"><span class="cite-bracket">&#91;</span>35<span class="cite-bracket">&#93;</span></a></sup> followed by an <a href="/wiki/Android_(operating_system)" title="Android (operating system)">Android</a> app in May 2013, at which time Duolingo had around 3 million users.<sup id="cite_ref-38" class="reference"><a href="#cite_note-38"><span class="cite-bracket">&#91;</span>36<span class="cite-bracket">&#93;</span></a></sup> By July 2013, it had grown to 5&#160;million users and was rated the No. 1 free education app in the <a href="/wiki/Google_Play" title="Google Play">Google Play Store</a>.<sup id="cite_ref-39" class="reference"><a href="#cite_note-39"><span class="cite-bracket">&#91;</span>37<span class="cite-bracket">&#93;</span></a></sup> </p><p>In February 2014, Duolingo announced that it had raised $20&#160;million from a Series&#160;C funding round led by <a href="/wiki/Kleiner_Perkins" title="Kleiner Perkins">Kleiner Caufield &amp; Byers</a>, with prior investors also participating.<sup id="cite_ref-TechCrunch1_40-0" class="reference"><a href="#cite_note-TechCrunch1-40"><span class="cite-bracket">&#91;</span>38<span class="cite-bracket">&#93;</span></a></sup> At this time, it had 34 employees, and reported about 25&#160;million <a href="/wiki/Registered_user" title="Registered user">registered users</a> and 12.5&#160;million active users;<sup id="cite_ref-TechCrunch1_40-1" class="reference"><a href="#cite_note-TechCrunch1-40"><span class="cite-bracket">&#91;</span>38<span class="cite-bracket">&#93;</span></a></sup> it later reported a figure closer to 60&#160;million users.<sup id="cite_ref-:2_41-0" class="reference"><a href="#cite_note-:2-41"><span class="cite-bracket">&#91;</span>39<span class="cite-bracket">&#93;</span></a></sup> </p><p>In June 2015, it announced that it had raised $45&#160;million from a Series&#160;D funding round led by <a href="/wiki/CapitalG" title="CapitalG">Google Capital</a>, bringing its total funding to $83.3&#160;million. The round valued the company at around $470&#160;million, with 100&#160;million registered users globally.<sup id="cite_ref-:1_30-1" class="reference"><a href="#cite_note-:1-30"><span class="cite-bracket">&#91;</span>28<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-:2_41-1" class="reference"><a href="#cite_note-:2-41"><span class="cite-bracket">&#91;</span>39<span class="cite-bracket">&#93;</span></a></sup> In April 2016, it was reported that Duolingo had more than 18&#160;million monthly users.<sup id="cite_ref-42" class="reference"><a href="#cite_note-42"><span class="cite-bracket">&#91;</span>40<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-43" class="reference"><a href="#cite_note-43"><span class="cite-bracket">&#91;</span>41<span class="cite-bracket">&#93;</span></a></sup> </p><p>In July 2017, Duolingo announced that it had raised $25&#160;million in a Series&#160;E funding round led by <a href="/wiki/Drive_Capital" title="Drive Capital">Drive Capital</a>, bringing its total funding to $108.3&#160;million. The round valued Duolingo at $700&#160;million, and the company reported passing 200&#160;million registered users, with 25&#160;million active users.<sup id="cite_ref-44" class="reference"><a href="#cite_note-44"><span class="cite-bracket">&#91;</span>42<span class="cite-bracket">&#93;</span></a></sup> It was reported that Duolingo had 95 employees.<sup id="cite_ref-Duolingo_45-0" class="reference"><a href="#cite_note-Duolingo-45"><span class="cite-bracket">&#91;</span>43<span class="cite-bracket">&#93;</span></a></sup> Funds from the Series&#160;E round would be directed toward creating initiatives such as a related educational flashcard app, TinyCards, and testbeds for initiatives related to reading and listening comprehension.<sup id="cite_ref-forbes.com_46-0" class="reference"><a href="#cite_note-forbes.com-46"><span class="cite-bracket">&#91;</span>44<span class="cite-bracket">&#93;</span></a></sup> On August 1, 2018, Duolingo surpassed 300&#160;million registered users.<sup id="cite_ref-social.techcrunch.com_47-0" class="reference"><a href="#cite_note-social.techcrunch.com-47"><span class="cite-bracket">&#91;</span>45<span class="cite-bracket">&#93;</span></a></sup> </p><p>In December 2019, it was announced that Duolingo raised $30&#160;million in a Series&#160;F funding round from <a href="/wiki/Alphabet_Inc." title="Alphabet Inc.">Alphabet</a>'s investment company, <a href="/wiki/CapitalG" title="CapitalG">CapitalG</a>.<sup id="cite_ref-lifestyle.livemint.com_23-1" class="reference"><a href="#cite_note-lifestyle.livemint.com-23"><span class="cite-bracket">&#91;</span>21<span class="cite-bracket">&#93;</span></a></sup> The round valued Duolingo at $1.5&#160;billion. Duolingo reported 30&#160;million active users at this time. The headcount at the company had increased to around two&#160;hundred, and new offices had been opened in <a href="/wiki/Seattle" title="Seattle">Seattle</a>, <a href="/wiki/New_York_City" title="New York City">New York</a>, and <a href="/wiki/Beijing" title="Beijing">Beijing</a>.<sup id="cite_ref-48" class="reference"><a href="#cite_note-48"><span class="cite-bracket">&#91;</span>46<span class="cite-bracket">&#93;</span></a></sup> Duolingo planned to use the funds to develop new products and further expand its team in sectors like engineering, business development, design, curriculum and content creators, community outreach, and marketing.<sup id="cite_ref-triblive.com_49-0" class="reference"><a href="#cite_note-triblive.com-49"><span class="cite-bracket">&#91;</span>47<span class="cite-bracket">&#93;</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Features_and_media">Features and media</h3></div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Duolingo,_mem-referenco,_1.jpeg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/b/b1/Duolingo%2C_mem-referenco%2C_1.jpeg/220px-Duolingo%2C_mem-referenco%2C_1.jpeg" decoding="async" width="220" height="351" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/b/b1/Duolingo%2C_mem-referenco%2C_1.jpeg/330px-Duolingo%2C_mem-referenco%2C_1.jpeg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/b/b1/Duolingo%2C_mem-referenco%2C_1.jpeg/440px-Duolingo%2C_mem-referenco%2C_1.jpeg 2x" data-file-width="1824" data-file-height="2912" /></a><figcaption>Duolingo in 2017</figcaption></figure> <p>In October 2013, Duolingo launched a <a href="/wiki/Crowdsourcing" title="Crowdsourcing">crowdsourced</a> language incubator.<sup id="cite_ref-50" class="reference"><a href="#cite_note-50"><span class="cite-bracket">&#91;</span>48<span class="cite-bracket">&#93;</span></a></sup> In March 2021, it announced that it would be ending its volunteer contributor program and donating money to its volunteer contributors who helped develop it. The company said that from now on, language courses would be maintained and developed by professional linguists aligning with <a href="/wiki/Common_European_Framework_of_Reference_for_Languages" title="Common European Framework of Reference for Languages">CEFR standards</a>.<sup id="cite_ref-51" class="reference"><a href="#cite_note-51"><span class="cite-bracket">&#91;</span>49<span class="cite-bracket">&#93;</span></a></sup> On June 28, 2021, Duolingo filed for an <a href="/wiki/Initial_public_offering" title="Initial public offering">initial public offering</a> on <a href="/wiki/Nasdaq" title="Nasdaq">NASDAQ</a> under the ticker DUOL.<sup id="cite_ref-52" class="reference"><a href="#cite_note-52"><span class="cite-bracket">&#91;</span>50<span class="cite-bracket">&#93;</span></a></sup> From August 2021 to June 2022, the Duolingo language learning app was removed from some app stores in China.<sup id="cite_ref-53" class="reference"><a href="#cite_note-53"><span class="cite-bracket">&#91;</span>51<span class="cite-bracket">&#93;</span></a></sup> In the early 2020s, Duolingo was noted for its viral videos on the social media platform <a href="/wiki/TikTok" title="TikTok">TikTok</a>.<sup id="cite_ref-54" class="reference"><a href="#cite_note-54"><span class="cite-bracket">&#91;</span>52<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-55" class="reference"><a href="#cite_note-55"><span class="cite-bracket">&#91;</span>53<span class="cite-bracket">&#93;</span></a></sup> </p><p>In August 2022, Duolingo overhauled its <a href="/wiki/Interface_(computing)" title="Interface (computing)">interface</a>, changing its course structure from a tree-like design, where users could choose from a range of lessons after completing previous ones, to a linear progression. This update has been criticized by users across social media outlets, such as <a href="/wiki/Reddit" title="Reddit">Reddit</a> and <a href="/wiki/Twitter" title="Twitter">Twitter</a>.<sup id="cite_ref-Businessweek_2022_22-1" class="reference"><a href="#cite_note-Businessweek_2022-22"><span class="cite-bracket">&#91;</span>20<span class="cite-bracket">&#93;</span></a></sup> CEO Luis von Ahn stated that there were no plans to reverse the changes—intended to simplify Duolingo for its new users—maintaining both the old and new versions would be difficult.<sup id="cite_ref-2022_redesign_56-0" class="reference"><a href="#cite_note-2022_redesign-56"><span class="cite-bracket">&#91;</span>54<span class="cite-bracket">&#93;</span></a></sup> In October 2022, Duolingo acquired Detroit-based animation studio Gunner; it is the studio that produces art assets and animation for Duolingo and Duolingo ABC and its marketing campaigns. </p><p>In March 2023, Duolingo officially announced the planned Duolingo Max, a subscription tier above Super Duolingo, in their blog.<sup id="cite_ref-57" class="reference"><a href="#cite_note-57"><span class="cite-bracket">&#91;</span>55<span class="cite-bracket">&#93;</span></a></sup> In July 2023, Duolingo launched a feature using the iOS widget feature. In October 2023, Duolingo released math and music courses in English and Spanish for <a href="/wiki/IOS" title="IOS">iOS</a> users.<sup id="cite_ref-58" class="reference"><a href="#cite_note-58"><span class="cite-bracket">&#91;</span>56<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-:4_59-0" class="reference"><a href="#cite_note-:4-59"><span class="cite-bracket">&#91;</span>57<span class="cite-bracket">&#93;</span></a></sup> </p><p>In 2024, Duolingo made several changes: it replaced some contractor tasks with <a href="/wiki/Artificial_intelligence" title="Artificial intelligence">AI</a> in January,<sup id="cite_ref-60" class="reference"><a href="#cite_note-60"><span class="cite-bracket">&#91;</span>58<span class="cite-bracket">&#93;</span></a></sup> launched the widget feature on Android in March,<sup id="cite_ref-61" class="reference"><a href="#cite_note-61"><span class="cite-bracket">&#91;</span>59<span class="cite-bracket">&#93;</span></a></sup> acquired Detroit-based design studio Hobbes, introduced Friend Streak in August, allowing students to share a streak together with their friends,<sup id="cite_ref-62" class="reference"><a href="#cite_note-62"><span class="cite-bracket">&#91;</span>60<span class="cite-bracket">&#93;</span></a></sup> and released math and music courses for Android in September.<sup id="cite_ref-63" class="reference"><a href="#cite_note-63"><span class="cite-bracket">&#91;</span>61<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-:5_64-0" class="reference"><a href="#cite_note-:5-64"><span class="cite-bracket">&#91;</span>62<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-65" class="reference"><a href="#cite_note-65"><span class="cite-bracket">&#91;</span>63<span class="cite-bracket">&#93;</span></a></sup> During Duocon 2024 Duolingo introduced various new features, including Video Call and mini games called Adventures. In October Duolingo introduced Duolingo Score.<sup id="cite_ref-66" class="reference"><a href="#cite_note-66"><span class="cite-bracket">&#91;</span>64<span class="cite-bracket">&#93;</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Products_and_services">Products and services</h2></div> <div class="mw-heading mw-heading3"><h3 id="Courses">Courses</h3></div> <div class="mw-heading mw-heading4"><h4 id="Language_courses">Language courses</h4></div> <p>Duolingo has 44 available language courses.<sup id="cite_ref-:3_9-1" class="reference"><a href="#cite_note-:3-9"><span class="cite-bracket">&#91;</span>7<span class="cite-bracket">&#93;</span></a></sup> </p> <style data-mw-deduplicate="TemplateStyles:r1184024115">.mw-parser-output .div-col{margin-top:0.3em;column-width:30em}.mw-parser-output .div-col-small{font-size:90%}.mw-parser-output .div-col-rules{column-rule:1px solid #aaa}.mw-parser-output .div-col dl,.mw-parser-output .div-col ol,.mw-parser-output .div-col ul{margin-top:0}.mw-parser-output .div-col li,.mw-parser-output .div-col dd{page-break-inside:avoid;break-inside:avoid-column}</style><div class="div-col" style="column-width: 15em;"> <ul><li><a href="/wiki/Arabic" title="Arabic">Arabic</a></li> <li><a href="/wiki/Catalan_language" title="Catalan language">Catalan</a><sup id="cite_ref-Spanish_67-0" class="reference"><a href="#cite_note-Spanish-67"><span class="cite-bracket">&#91;</span>c<span class="cite-bracket">&#93;</span></a></sup></li> <li><a href="/wiki/Cantonese" title="Cantonese">Chinese (Cantonese)</a><sup id="cite_ref-Mandarin_68-0" class="reference"><a href="#cite_note-Mandarin-68"><span class="cite-bracket">&#91;</span>d<span class="cite-bracket">&#93;</span></a></sup></li> <li><a href="/wiki/Mandarin_Chinese" title="Mandarin Chinese">Chinese (Mandarin)</a></li> <li><a href="/wiki/Czech_language" title="Czech language">Czech</a></li> <li><a href="/wiki/Danish_language" title="Danish language">Danish</a></li> <li><a href="/wiki/Dutch_language" title="Dutch language">Dutch</a></li> <li><a href="/wiki/English_language" title="English language">English</a></li> <li><a href="/wiki/AP_English_Language_and_Composition" title="AP English Language and Composition">English (Intermediate)</a></li> <li><a href="/wiki/Esperanto" title="Esperanto">Esperanto</a></li> <li><a href="/wiki/Finnish_language" title="Finnish language">Finnish</a></li> <li><a href="/wiki/French_language" title="French language">French</a></li> <li><a href="/wiki/German_language" title="German language">German</a></li> <li><a href="/wiki/Greek_language" title="Greek language">Greek</a></li> <li><a href="/wiki/Guarani_language" title="Guarani language">Guarani</a><sup id="cite_ref-Spanish_67-1" class="reference"><a href="#cite_note-Spanish-67"><span class="cite-bracket">&#91;</span>c<span class="cite-bracket">&#93;</span></a></sup></li> <li><a href="/wiki/Haitian_Creole" title="Haitian Creole">Haitian Creole</a></li> <li><a href="/wiki/Hawaiian_language" title="Hawaiian language">Hawaiian</a></li> <li><a href="/wiki/Hebrew_language" title="Hebrew language">Hebrew</a></li> <li><a href="/wiki/Valyrian_languages" title="Valyrian languages">High Valyrian</a></li> <li><a href="/wiki/Hindi" title="Hindi">Hindi</a></li> <li><a href="/wiki/Hungarian_language" title="Hungarian language">Hungarian</a></li> <li><a href="/wiki/Indonesian_language" title="Indonesian language">Indonesian</a></li> <li><a href="/wiki/Irish_language" title="Irish language">Irish</a></li> <li><a href="/wiki/Italian_language" title="Italian language">Italian</a></li> <li><a href="/wiki/Japanese_language" title="Japanese language">Japanese</a></li> <li><a href="/wiki/Klingon_language" title="Klingon language">Klingon</a></li> <li><a href="/wiki/Korean_language" title="Korean language">Korean</a></li> <li><a href="/wiki/Latin" title="Latin">Latin</a></li> <li><a href="/wiki/Navajo_language" title="Navajo language">Navajo</a></li> <li><a href="/wiki/Norwegian_language" title="Norwegian language">Norwegian</a></li> <li><a href="/wiki/Polish_language" title="Polish language">Polish</a></li> <li><a href="/wiki/Portuguese_language" title="Portuguese language">Portuguese</a></li> <li><a href="/wiki/Romanian_language" title="Romanian language">Romanian</a></li> <li><a href="/wiki/Russian_language" title="Russian language">Russian</a></li> <li><a href="/wiki/Scottish_Gaelic" title="Scottish Gaelic">Scottish Gaelic</a></li> <li><a href="/wiki/Spanish_language" title="Spanish language">Spanish</a></li> <li><a href="/wiki/Swahili_language" title="Swahili language">Swahili</a></li> <li><a href="/wiki/Swedish_language" title="Swedish language">Swedish</a></li> <li><a href="/wiki/Turkish_language" title="Turkish language">Turkish</a></li> <li><a href="/wiki/Ukrainian_language" title="Ukrainian language">Ukrainian</a></li> <li><a href="/wiki/Vietnamese_language" title="Vietnamese language">Vietnamese</a></li> <li><a href="/wiki/Welsh_language" title="Welsh language">Welsh</a></li> <li><a href="/wiki/Yiddish" title="Yiddish">Yiddish</a></li> <li><a href="/wiki/Zulu_language" title="Zulu language">Zulu</a></li></ul> </div> <div class="mw-heading mw-heading4"><h4 id="Duolingo_Math">Duolingo Math</h4></div> <p>Duolingo Math is an app course for learning <a href="/wiki/Elementary_mathematics" title="Elementary mathematics">elementary mathematics</a>. It was announced on YouTube on August 27, 2022, at the Duocon 2022 event.<sup id="cite_ref-69" class="reference"><a href="#cite_note-69"><span class="cite-bracket">&#91;</span>65<span class="cite-bracket">&#93;</span></a></sup> Duolingo Math covers math topics through an interactive and gradual approach. It starts with basic arithmetic—addition, subtraction, multiplication, and division. The app also teaches fractions and decimals, focusing on comparing, converting, and calculating. Geometry lessons include understanding shapes, calculating area and volume. Measurement is another focus, with exercises on using and converting different units like length and time. Duolingo also allows its users to play math games.<sup id="cite_ref-70" class="reference"><a href="#cite_note-70"><span class="cite-bracket">&#91;</span>66<span class="cite-bracket">&#93;</span></a></sup> </p> <div class="mw-heading mw-heading4"><h4 id="Duolingo_Music">Duolingo Music</h4></div> <p>In March 2023, Duolingo was reportedly developing a new music course that would allow users to learn how to read and play music through its gamified learning experience.<sup id="cite_ref-71" class="reference"><a href="#cite_note-71"><span class="cite-bracket">&#91;</span>67<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-72" class="reference"><a href="#cite_note-72"><span class="cite-bracket">&#91;</span>68<span class="cite-bracket">&#93;</span></a></sup> On October 11, 2023, Duolingo formally unveiled Duolingo Music in a <a href="/wiki/YouTube_Shorts" title="YouTube Shorts">YouTube Short</a>,<sup id="cite_ref-:4_59-1" class="reference"><a href="#cite_note-:4-59"><span class="cite-bracket">&#91;</span>57<span class="cite-bracket">&#93;</span></a></sup> a new platform within the existing app that provides basic music learning through <a href="/wiki/Piano" title="Piano">piano</a> and <a href="/wiki/Sheet_music" title="Sheet music">sheet music</a> lessons.<sup id="cite_ref-73" class="reference"><a href="#cite_note-73"><span class="cite-bracket">&#91;</span>69<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-74" class="reference"><a href="#cite_note-74"><span class="cite-bracket">&#91;</span>70<span class="cite-bracket">&#93;</span></a></sup> As of April&#160;2024<sup class="plainlinks noexcerpt noprint asof-tag update" style="display:none;"><a class="external text" href="https://en.wikipedia.org/w/index.php?title=Duolingo&amp;action=edit">&#91;update&#93;</a></sup>, it is currently available on iOS and Android devices.<sup id="cite_ref-75" class="reference"><a href="#cite_note-75"><span class="cite-bracket">&#91;</span>71<span class="cite-bracket">&#93;</span></a></sup> Since August 2024, users can practice music by playing pop songs in the course.<sup id="cite_ref-76" class="reference"><a href="#cite_note-76"><span class="cite-bracket">&#91;</span>72<span class="cite-bracket">&#93;</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Subscriptions">Subscriptions</h3></div> <div class="mw-heading mw-heading4"><h4 id="Super_Duolingo">Super Duolingo</h4></div> <p>Most of Duolingo's language learning features are free, with periodic advertising in its mobile and web browser applications, which users can remove by paying a subscription fee or promoting referral links.<sup id="cite_ref-77" class="reference"><a href="#cite_note-77"><span class="cite-bracket">&#91;</span>73<span class="cite-bracket">&#93;</span></a></sup> This program, known as Super Duolingo, includes benefits such as unlimited hearts (retries), personalized practice, no ads, focused listening and speaking exercises, free and unlimited entries to legendary challenges and side quests, and is otherwise identical to Duolingo for Schools.<sup id="cite_ref-78" class="reference"><a href="#cite_note-78"><span class="cite-bracket">&#91;</span>74<span class="cite-bracket">&#93;</span></a></sup> <sup id="cite_ref-79" class="reference"><a href="#cite_note-79"><span class="cite-bracket">&#91;</span>75<span class="cite-bracket">&#93;</span></a></sup> </p> <div class="mw-heading mw-heading4"><h4 id="Duolingo_Max">Duolingo Max</h4></div> <p>Duolingo Max is a subscription above Super Duolingo that adds additional functions using <a href="/wiki/Generative_artificial_intelligence" title="Generative artificial intelligence">generative AI</a>: RolePlay, an AI conversation partner, Explain My Answer, which breaks down the rules with a modified <a href="/wiki/GPT-4" title="GPT-4">GPT-4</a> when the user makes a mistake, and Video Call, where users can have video chat with one of the characters, Lily. Intended to provide further immersion through "free-flowing conversation",<sup id="cite_ref-80" class="reference"><a href="#cite_note-80"><span class="cite-bracket">&#91;</span>76<span class="cite-bracket">&#93;</span></a></sup> it is available in selected courses and markets.<sup id="cite_ref-81" class="reference"><a href="#cite_note-81"><span class="cite-bracket">&#91;</span>77<span class="cite-bracket">&#93;</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Duolingo_for_Schools">Duolingo for Schools</h3></div> <p>Duolingo for Schools is designed to help teachers use Duolingo in their classrooms. It allows teachers to create classrooms, assign lessons, track student progress, and personalize learning.<sup id="cite_ref-82" class="reference"><a href="#cite_note-82"><span class="cite-bracket">&#91;</span>78<span class="cite-bracket">&#93;</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Duolingo_ABC">Duolingo ABC</h3></div> <p>Duolingo ABC is a free app designed for young children to learn letters, their sounds, phonics, and other early reading concepts. Released in 2020, it does not contain ads or in-app purchases. As of April 2024, iOS and Android versions are available, but only in English.<sup id="cite_ref-math_8-1" class="reference"><a href="#cite_note-math-8"><span class="cite-bracket">&#91;</span>6<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-83" class="reference"><a href="#cite_note-83"><span class="cite-bracket">&#91;</span>79<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-84" class="reference"><a href="#cite_note-84"><span class="cite-bracket">&#91;</span>80<span class="cite-bracket">&#93;</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Duolingo_piano">Duolingo piano</h3></div> <p>The <b>Duolingo x Loog Piano</b> is a 37-key portable digital piano created through a partnership between Duolingo and Loog. It features <a href="/wiki/Velocity-sensitive" class="mw-redirect" title="Velocity-sensitive">velocity-sensitive</a> keys, built-in speakers, and ports for USB-C, a <a href="/wiki/Sustain_pedal" title="Sustain pedal">sustain pedal</a>, and headphones. The piano is designed to work with Duolingo's music lessons.<sup id="cite_ref-85" class="reference"><a href="#cite_note-85"><span class="cite-bracket">&#91;</span>81<span class="cite-bracket">&#93;</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Duolingo_English_test">Duolingo English test</h3></div> <style data-mw-deduplicate="TemplateStyles:r1236090951">.mw-parser-output .hatnote{font-style:italic}.mw-parser-output div.hatnote{padding-left:1.6em;margin-bottom:0.5em}.mw-parser-output .hatnote i{font-style:normal}.mw-parser-output .hatnote+link+.hatnote{margin-top:-0.5em}@media print{body.ns-0 .mw-parser-output .hatnote{display:none!important}}</style><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/Duolingo_English_Test" title="Duolingo English Test">Duolingo English Test</a></div> <p>The Duolingo English Test (DET) is an online English proficiency test that measures proficiency in reading, writing, speaking, and listening in English. It is a computer-based test scored on a scale of 10–160, with scores above 120 considered English proficiency. The test's questions algorithmically adjust to the test-takers' ability level. The test's certificate is reportedly accepted by over 5,500 programs internationally,<sup id="cite_ref-86" class="reference"><a href="#cite_note-86"><span class="cite-bracket">&#91;</span>82<span class="cite-bracket">&#93;</span></a></sup> albeit with exceptions.<sup id="cite_ref-87" class="reference"><a href="#cite_note-87"><span class="cite-bracket">&#91;</span>83<span class="cite-bracket">&#93;</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Learning_model">Learning model</h2></div> <p>On Duolingo, learners learn by engaging with the language. Users complete lessons using words they are learning.<sup id="cite_ref-88" class="reference"><a href="#cite_note-88"><span class="cite-bracket">&#91;</span>84<span class="cite-bracket">&#93;</span></a></sup> Duolingo uses a <a href="/wiki/Gamification" title="Gamification">gamified approach</a> to language learning, with lessons that incorporate translating, interactive exercises, quizzes, and stories.<sup id="cite_ref-89" class="reference"><a href="#cite_note-89"><span class="cite-bracket">&#91;</span>85<span class="cite-bracket">&#93;</span></a></sup> It also uses an algorithm that adapts to each learner and can provide personalized feedback and recommendations. Lessons are designed to be brief, allowing users to learn in manageable chunks.<sup id="cite_ref-90" class="reference"><a href="#cite_note-90"><span class="cite-bracket">&#91;</span>86<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-91" class="reference"><a href="#cite_note-91"><span class="cite-bracket">&#91;</span>87<span class="cite-bracket">&#93;</span></a></sup> The app has a personalized <a href="/wiki/Multi-armed_bandit" title="Multi-armed bandit">bandit algorithm</a> system (later the <a href="/wiki/A/B_testing" title="A/B testing">A/B tested</a> variant <i>recovering difference <a href="/wiki/Softmax_function" title="Softmax function">softmax algorithm</a></i>) that determines the daily notification that will be sent out to the user.<sup id="cite_ref-92" class="reference"><a href="#cite_note-92"><span class="cite-bracket">&#91;</span>88<span class="cite-bracket">&#93;</span></a></sup> </p><p>Duolingo provides a competitive space,<sup id="cite_ref-93" class="reference"><a href="#cite_note-93"><span class="cite-bracket">&#91;</span>89<span class="cite-bracket">&#93;</span></a></sup> such as in Leagues, where people can compete with randomly selected worldwide player groupings of up to 30 users. Users can also create their own avatars and compete against each other in Duolingo Clash.<sup id="cite_ref-94" class="reference"><a href="#cite_note-94"><span class="cite-bracket">&#91;</span>90<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-95" class="reference"><a href="#cite_note-95"><span class="cite-bracket">&#91;</span>91<span class="cite-bracket">&#93;</span></a></sup> Rankings in leagues are determined by the number of "XP" (<i>experience points</i>) earned in a week. Badges in Duolingo represent achievements earned from completing specific objectives.<sup id="cite_ref-96" class="reference"><a href="#cite_note-96"><span class="cite-bracket">&#91;</span>92<span class="cite-bracket">&#93;</span></a></sup> </p><p>Duolingo has a widget feature on iOS and Android. The widget feature initially started as Duolingo's annual hackathon project. The iOS widget has 39 illustrations designed by Kyle Ruane that were intended to be another daily reminder to complete lessons. On the top part of the widgets is the user's <i>daily streak</i>. On the Duolingo Blog, they wrote that they "decided to come up with a series of illustrations that would show Duo’s mood at different parts of the day".<sup id="cite_ref-:5_64-1" class="reference"><a href="#cite_note-:5-64"><span class="cite-bracket">&#91;</span>62<span class="cite-bracket">&#93;</span></a></sup> Any lesson completed in Duolingo will count towards the user's <i>daily streak</i>.<sup id="cite_ref-97" class="reference"><a href="#cite_note-97"><span class="cite-bracket">&#91;</span>93<span class="cite-bracket">&#93;</span></a></sup> The <i>daily streak</i>'s <a href="/wiki/Symbol" title="Symbol">visual symbol</a> in the app is fire. Duolingo's "Friend Streak" lets users maintain streaks with up to five friends.<sup id="cite_ref-98" class="reference"><a href="#cite_note-98"><span class="cite-bracket">&#91;</span>94<span class="cite-bracket">&#93;</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Business_model">Business model</h2></div> <p>Duolingo operates on a freemium business model, offering free access to its learning platforms with ads. Revenue is primarily generated through subscriptions, which remove ads, and provide other perks like unlimited hearts and generative AI. The app also generates income from in-app purchases of virtual currency (Gems) and power-ups that enhance the learning experience. Another key revenue stream is the Duolingo English Test (DET), a low-cost English proficiency test.<sup id="cite_ref-99" class="reference"><a href="#cite_note-99"><span class="cite-bracket">&#91;</span>95<span class="cite-bracket">&#93;</span></a></sup> </p><p>In April 2020, it passed one million paid subscribers;<sup id="cite_ref-100" class="reference"><a href="#cite_note-100"><span class="cite-bracket">&#91;</span>96<span class="cite-bracket">&#93;</span></a></sup> it reached 2.9 million in March 2022,<sup id="cite_ref-101" class="reference"><a href="#cite_note-101"><span class="cite-bracket">&#91;</span>97<span class="cite-bracket">&#93;</span></a></sup> and 4.8 million at the end of March 2023.<sup id="cite_ref-102" class="reference"><a href="#cite_note-102"><span class="cite-bracket">&#91;</span>98<span class="cite-bracket">&#93;</span></a></sup> As of June 2024 Duolingo has 8 million paying subscribers. </p><p>Duolingo had revenue of $531 million in 2023, compared to $250.77 million in 2021,<sup id="cite_ref-103" class="reference"><a href="#cite_note-103"><span class="cite-bracket">&#91;</span>99<span class="cite-bracket">&#93;</span></a></sup> $36 million in 2018,<sup id="cite_ref-Adams_104-0" class="reference"><a href="#cite_note-Adams-104"><span class="cite-bracket">&#91;</span>100<span class="cite-bracket">&#93;</span></a></sup> $13 million in 2017,<sup id="cite_ref-social.techcrunch.com_47-1" class="reference"><a href="#cite_note-social.techcrunch.com-47"><span class="cite-bracket">&#91;</span>45<span class="cite-bracket">&#93;</span></a></sup> and $1 million in 2016. In May 2022, it was reported that 6.8% of its monthly active users paid for the ad-free version of the app.<sup id="cite_ref-105" class="reference"><a href="#cite_note-105"><span class="cite-bracket">&#91;</span>101<span class="cite-bracket">&#93;</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Reception">Reception</h2></div> <div class="mw-heading mw-heading3"><h3 id="Effectiveness">Effectiveness</h3></div> <p>A 2017 study found no significant difference between elementary students learning Spanish through the "gamification" of the Duolingo app and those learning in classroom environments, with both groups demonstrating a similar increase in achievements and <a href="/wiki/Self-efficacy" title="Self-efficacy">self-efficacy</a>.<sup id="cite_ref-106" class="reference"><a href="#cite_note-106"><span class="cite-bracket">&#91;</span>102<span class="cite-bracket">&#93;</span></a></sup> </p><p>Duolingo's occasional use of 'erratic' phrases—such as "The bride is a woman and the groom is a hedgehog" or "The man eats ice cream with mustard"<sup id="cite_ref-:6_107-0" class="reference"><a href="#cite_note-:6-107"><span class="cite-bracket">&#91;</span>103<span class="cite-bracket">&#93;</span></a></sup>—is reportedly derived from research published in 2018 by psychologists at <a href="/wiki/Ghent_University" title="Ghent University">Ghent University</a> in Belgium,<sup id="cite_ref-108" class="reference"><a href="#cite_note-108"><span class="cite-bracket">&#91;</span>104<span class="cite-bracket">&#93;</span></a></sup> which concluded that such "semantically unpredictable sentences" were more effective for language learning than conventional and predictable phrases, based on the concept of "reward prediction errors", in which unexpected or surprising outcomes are more rewarding and thus encourage further learning.<sup id="cite_ref-109" class="reference"><a href="#cite_note-109"><span class="cite-bracket">&#91;</span>105<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-:6_107-1" class="reference"><a href="#cite_note-:6-107"><span class="cite-bracket">&#91;</span>103<span class="cite-bracket">&#93;</span></a></sup> </p><p>A 2022 study on adults using Duolingo as their only language learning tool, published in the journal <i><a href="/wiki/Foreign_Language_Annals" title="Foreign Language Annals">Foreign Language Annals</a></i>, found that participants who completed a course had similar reading and listening proficiency to university students after four semesters of study, concluding that Duolingo could be an effective tool for language learning.<sup id="cite_ref-110" class="reference"><a href="#cite_note-110"><span class="cite-bracket">&#91;</span>106<span class="cite-bracket">&#93;</span></a></sup> Another 2022 study of Malaysian students learning French, published by the <a href="/wiki/National_University_of_Malaysia" class="mw-redirect" title="National University of Malaysia">National University of Malaysia</a> Press, found that the app facilitated the acquisition of vocabulary and concluded that it was "well suited" for beginners in this regard.<sup id="cite_ref-111" class="reference"><a href="#cite_note-111"><span class="cite-bracket">&#91;</span>107<span class="cite-bracket">&#93;</span></a></sup> </p><p>According to Duolingo's own 2021 study, five sections of the app are roughly equivalent to five semesters of university instruction, and Duolingo is an "effective tool [...] at an intermediate level".<sup id="cite_ref-112" class="reference"><a href="#cite_note-112"><span class="cite-bracket">&#91;</span>108<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-113" class="reference"><a href="#cite_note-113"><span class="cite-bracket">&#91;</span>109<span class="cite-bracket">&#93;</span></a></sup> A 2023 study funded by Duolingo concluded that Duolingo English learners did not significantly learn much grammar.<sup id="cite_ref-114" class="reference"><a href="#cite_note-114"><span class="cite-bracket">&#91;</span>110<span class="cite-bracket">&#93;</span></a></sup> Duolingo English learners in <a href="/wiki/Colombia" title="Colombia">Colombia</a> and <a href="/wiki/Spain" title="Spain">Spain</a> were found to gain significantly more proficiency than students in a classroom, except for listening.<sup id="cite_ref-115" class="reference"><a href="#cite_note-115"><span class="cite-bracket">&#91;</span>111<span class="cite-bracket">&#93;</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Criticism">Criticism</h3></div> <p>Some language professionals have criticized the app for its limitations and gamified design.<sup id="cite_ref-116" class="reference"><a href="#cite_note-116"><span class="cite-bracket">&#91;</span>112<span class="cite-bracket">&#93;</span></a></sup> Others have pointed out that Duolingo and similar apps can be a starting point but lack the human interaction required to be fluent in a language and for real-life conversations.<sup id="cite_ref-117" class="reference"><a href="#cite_note-117"><span class="cite-bracket">&#91;</span>113<span class="cite-bracket">&#93;</span></a></sup> For instance, Bruno Estigarribia stated that, as of 2019, the Guarani course was "seemingly in a development phase" and that it "had many inconsistencies". He added it could serve as a complement to one's studies, but it would not "magically teach" the language.<sup id="cite_ref-118" class="reference"><a href="#cite_note-118"><span class="cite-bracket">&#91;</span>114<span class="cite-bracket">&#93;</span></a></sup> Players have also reported that "gamification" has led to cheating, hacking, and incentivized game strategies that conflict with actual learning.<sup id="cite_ref-kotaku-cheaters_119-0" class="reference"><a href="#cite_note-kotaku-cheaters-119"><span class="cite-bracket">&#91;</span>115<span class="cite-bracket">&#93;</span></a></sup> </p><p>In March 2022, Duolingo forums were discontinued,<sup id="cite_ref-120" class="reference"><a href="#cite_note-120"><span class="cite-bracket">&#91;</span>116<span class="cite-bracket">&#93;</span></a></sup> and Sentence discussions became read-only.<sup id="cite_ref-121" class="reference"><a href="#cite_note-121"><span class="cite-bracket">&#91;</span>117<span class="cite-bracket">&#93;</span></a></sup> The change has been criticized on some social media sites. </p><p>In January 2023, Duolingo's data on over 2.6 million users' usernames, names, and phone numbers was sold in a hacker forum. Duolingo later stated that they would investigate the "dark web post".<sup id="cite_ref-122" class="reference"><a href="#cite_note-122"><span class="cite-bracket">&#91;</span>118<span class="cite-bracket">&#93;</span></a></sup> They concluded that the data was obtained by scraping publicly available information based on an exposed <a href="/wiki/API" title="API">application programming interface</a> (API).<sup id="cite_ref-123" class="reference"><a href="#cite_note-123"><span class="cite-bracket">&#91;</span>119<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-124" class="reference"><a href="#cite_note-124"><span class="cite-bracket">&#91;</span>120<span class="cite-bracket">&#93;</span></a></sup> Duolingo's spokesperson states that the API is intentionally publicly visible. </p><p>Since the end of October 2023, Duolingo has stopped updating its Welsh course to "focus on languages in higher demand". Some users criticized this decision because it came at the expense of learners of a language with limited resources on the market and the potential halting of the <a href="/wiki/Welsh_Government" title="Welsh Government">Welsh Government</a><span class="nowrap" style="padding-left:0.1em;">&#39;s</span> "Cymraeg 2050" strategy to promote Welsh language learning.<sup id="cite_ref-125" class="reference"><a href="#cite_note-125"><span class="cite-bracket">&#91;</span>121<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-126" class="reference"><a href="#cite_note-126"><span class="cite-bracket">&#91;</span>122<span class="cite-bracket">&#93;</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Awards">Awards</h3></div> <p>In 2013, <a href="/wiki/Apple_Inc." title="Apple Inc.">Apple</a> chose Duolingo as its iPhone App of the Year, a first for an educational application.<sup id="cite_ref-gigaom_127-0" class="reference"><a href="#cite_note-gigaom-127"><span class="cite-bracket">&#91;</span>123<span class="cite-bracket">&#93;</span></a></sup> That year, Duolingo ranked No.<span class="nowrap">&#160;</span>7 on <i><a href="/wiki/Fast_Company" title="Fast Company">Fast Company</a></i><span class="nowrap" style="padding-left:0.1em;">&#39;s</span> "The World's Most Innovative Companies: Education Honorees" list "for crowdsourcing web translation by turning it into a free language-learning program".<sup id="cite_ref-128" class="reference"><a href="#cite_note-128"><span class="cite-bracket">&#91;</span>124<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-129" class="reference"><a href="#cite_note-129"><span class="cite-bracket">&#91;</span>125<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-130" class="reference"><a href="#cite_note-130"><span class="cite-bracket">&#91;</span>126<span class="cite-bracket">&#93;</span></a></sup> Duolingo won Best Education Startup at the 2014 <a href="/wiki/Crunchies" title="Crunchies">Crunchies</a>,<sup id="cite_ref-duolingo.com_131-0" class="reference"><a href="#cite_note-duolingo.com-131"><span class="cite-bracket">&#91;</span>127<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-132" class="reference"><a href="#cite_note-132"><span class="cite-bracket">&#91;</span>128<span class="cite-bracket">&#93;</span></a></sup> and was the most downloaded 'education app' in Google Play in 2013 and 2014.<sup id="cite_ref-TNW_133-0" class="reference"><a href="#cite_note-TNW-133"><span class="cite-bracket">&#91;</span>129<span class="cite-bracket">&#93;</span></a></sup> In July 2020, <i><a href="/wiki/PCMag" title="PCMag">PCMag</a></i> named it "The Best Free Language Learning App".<sup id="cite_ref-134" class="reference"><a href="#cite_note-134"><span class="cite-bracket">&#91;</span>130<span class="cite-bracket">&#93;</span></a></sup> </p><p>As a company, Duolingo has likewise won several awards and recognitions. In 2015, it was announced as that year's Index Award winner in the Play &amp; Learning category by <a href="/wiki/The_Index_Project" title="The Index Project">The Index Project</a>.<sup id="cite_ref-135" class="reference"><a href="#cite_note-135"><span class="cite-bracket">&#91;</span>131<span class="cite-bracket">&#93;</span></a></sup> It won <a href="/wiki/Inc._(magazine)" title="Inc. (magazine)"><i>Inc.</i> magazine</a>'s Best Workplaces 2018,<sup id="cite_ref-136" class="reference"><a href="#cite_note-136"><span class="cite-bracket">&#91;</span>132<span class="cite-bracket">&#93;</span></a></sup> made <a href="/wiki/Entrepreneur_(magazine)" title="Entrepreneur (magazine)"><i>Entrepreneur</i> magazine</a>'s Top Company Culture List 2018,<sup id="cite_ref-137" class="reference"><a href="#cite_note-137"><span class="cite-bracket">&#91;</span>133<span class="cite-bracket">&#93;</span></a></sup> was among <a href="/wiki/CNBC" title="CNBC">CNBC</a>'s "Disruptor 50" lists for 2018 and 2019,<sup id="cite_ref-138" class="reference"><a href="#cite_note-138"><span class="cite-bracket">&#91;</span>134<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-139" class="reference"><a href="#cite_note-139"><span class="cite-bracket">&#91;</span>135<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-140" class="reference"><a href="#cite_note-140"><span class="cite-bracket">&#91;</span>136<span class="cite-bracket">&#93;</span></a></sup> and was ranked as one of <a href="/wiki/Time_(magazine)" title="Time (magazine)"><i>TIME</i> magazine</a>'s 50 Genius Companies.<sup id="cite_ref-141" class="reference"><a href="#cite_note-141"><span class="cite-bracket">&#91;</span>137<span class="cite-bracket">&#93;</span></a></sup> Duolingo was named one of <i><a href="/wiki/Forbes" title="Forbes">Forbes</a></i><span class="nowrap" style="padding-left:0.1em;">&#39;s</span> "Next Billion-Dollar Startups 2019".<sup id="cite_ref-142" class="reference"><a href="#cite_note-142"><span class="cite-bracket">&#91;</span>138<span class="cite-bracket">&#93;</span></a></sup> In 2023, Duolingo won a Design Award during the 2023 edition of the <a href="/wiki/Apple_Design_Awards" title="Apple Design Awards">Apple Design Awards</a>.<sup id="cite_ref-143" class="reference"><a href="#cite_note-143"><span class="cite-bracket">&#91;</span>139<span class="cite-bracket">&#93;</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Image_and_brand">Image and brand</h2></div> <div class="mw-heading mw-heading3"><h3 id="Duolingo's_characters"><span id="Duolingo.27s_characters"></span>Duolingo's characters</h3></div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Duo_from_Duolingo.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/en/thumb/6/64/Duo_from_Duolingo.svg/220px-Duo_from_Duolingo.svg.png" decoding="async" width="220" height="224" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/6/64/Duo_from_Duolingo.svg/330px-Duo_from_Duolingo.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/6/64/Duo_from_Duolingo.svg/440px-Duo_from_Duolingo.svg.png 2x" data-file-width="313" data-file-height="319" /></a><figcaption>Duo, the mascot of Duolingo</figcaption></figure> <p>Duolingo has <a href="/wiki/Mascot" title="Mascot">brand characters</a> that were used for <a href="/wiki/Customer_engagement" title="Customer engagement">engagement</a>.<sup id="cite_ref-144" class="reference"><a href="#cite_note-144"><span class="cite-bracket">&#91;</span>140<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-145" class="reference"><a href="#cite_note-145"><span class="cite-bracket">&#91;</span>141<span class="cite-bracket">&#93;</span></a></sup> Some of these characters include:<sup id="cite_ref-146" class="reference"><a href="#cite_note-146"><span class="cite-bracket">&#91;</span>142<span class="cite-bracket">&#93;</span></a></sup> </p> <ul><li><b>Duo</b>: The green owl mascot. Duo serves as the motivational face of the app, encouraging users to complete their lessons and maintain their learning streaks. It's also famous for sending reminders to practice, often with a humorous or slightly dramatic tone.</li> <li><b>Lily</b>: A sarcastic teenager with a witty and somewhat apathetic personality.</li> <li><b>Zari</b>: A confident and enthusiastic young girl.</li> <li><b>Eddy</b>: An optimistic character with a passion for sports, father of Junior.</li> <li><b>Vikram</b>: A calm and responsible professional.</li> <li><b>Junior</b>: A curious and eager young boy.</li> <li><b>Oscar</b>: A prim lover of art and culture.</li> <li><b>Lin</b>: A creative and adventurous artist and motorcyclist.</li> <li><b>Lucy</b>: A venturesome elderly lady, grandmother of Lin.</li> <li><b>Bea</b>: A smart and energetic young girl.</li> <li><b>Falstaff</b>: An older, intellectual grizzly bear with a love for literature.</li></ul> <p>All characters mentioned above are human, with the exceptions of Duo, who is an <a href="/wiki/Owl" title="Owl">owl</a>, and Falstaff, who is a <a href="/wiki/Bear" title="Bear">bear</a>. </p> <div class="mw-heading mw-heading3"><h3 id="In_popular_culture">In popular culture</h3></div> <p>Due to the app's frequent reminder notifications, Duolingo's mascot, a green cartoon <a href="/wiki/Owl" title="Owl">owl</a> named Duo, has been the subject of <a href="/wiki/Internet_meme" title="Internet meme">Internet memes</a> antagonising him, with the character often depicted stalking or threatening users if they do not continue using the app.<sup id="cite_ref-147" class="reference"><a href="#cite_note-147"><span class="cite-bracket">&#91;</span>143<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-148" class="reference"><a href="#cite_note-148"><span class="cite-bracket">&#91;</span>144<span class="cite-bracket">&#93;</span></a></sup> </p><p>Duolingo has leaned into its online reputation and has adjusted its social media and marketing strategies accordingly.<sup id="cite_ref-149" class="reference"><a href="#cite_note-149"><span class="cite-bracket">&#91;</span>145<span class="cite-bracket">&#93;</span></a></sup> Acknowledging the meme, Duolingo released a video on <a href="/wiki/April_Fools%27_Day" title="April Fools&#39; Day">April Fools' Day</a> 2019, depicting a facetious new feature called "Duolingo Push". In the video, users of "Duolingo Push" are reminded to use the app by Duo himself (depicted by a <a href="/wiki/Person" title="Person">person</a> wearing a Duolingo <a href="/wiki/Costumed_character" class="mw-redirect" title="Costumed character">mascot costume</a>), who stares at and follows them until they comply.<sup id="cite_ref-150" class="reference"><a href="#cite_note-150"><span class="cite-bracket">&#91;</span>146<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-151" class="reference"><a href="#cite_note-151"><span class="cite-bracket">&#91;</span>147<span class="cite-bracket">&#93;</span></a></sup> It was also acknowledged during Duolingo's 2022 April Fools' Day video, "Lawyer Fights Duolingo Owl for $2,700,000", where a fictitious law firm fights for those that have been harmed by Duolingo's owl mascot.<sup id="cite_ref-152" class="reference"><a href="#cite_note-152"><span class="cite-bracket">&#91;</span>148<span class="cite-bracket">&#93;</span></a></sup> This was further referenced by the company in its 2024 April Fools' Day skit "Duo on Ice", in which the owl, in a mix of Spanish and English, admitted to having an appetite for human flesh, and if the user failed to continue their streak, they would "eat their head like a <a href="/wiki/Mantis" title="Mantis">praying mantis</a>."<sup id="cite_ref-153" class="reference"><a href="#cite_note-153"><span class="cite-bracket">&#91;</span>149<span class="cite-bracket">&#93;</span></a></sup> In February 2020, as part of the company's partnership with the developers of the video game <i><a href="/wiki/Angry_Birds_2" title="Angry Birds 2">Angry Birds 2</a></i>, a skit depicting Duo and the red Angry Bird attacking a crowd was uploaded.<sup id="cite_ref-154" class="reference"><a href="#cite_note-154"><span class="cite-bracket">&#91;</span>150<span class="cite-bracket">&#93;</span></a></sup> </p><p>In November 2019, <i><a href="/wiki/Saturday_Night_Live" title="Saturday Night Live">Saturday Night Live</a></i> parodied Duolingo in a sketch where adults learned to communicate with children by using a fictitious course called "Duolingo for Talking to Children".<sup id="cite_ref-155" class="reference"><a href="#cite_note-155"><span class="cite-bracket">&#91;</span>151<span class="cite-bracket">&#93;</span></a></sup> </p><p>The 2023 film <i><a href="/wiki/Barbie_(film)" title="Barbie (film)">Barbie</a></i> contains a running gag where the husband of disgruntled <a href="/wiki/Mattel" title="Mattel">Mattel</a> employee Gloria uses Duolingo to learn Spanish, Gloria's native language. </p> <div class="mw-heading mw-heading3"><h3 id="Duocon">Duocon</h3></div> <p>Duocon is Duolingo's annual conference, launched in 2019, aimed at gathering Duolingo users, language enthusiasts, and educational technology professionals. The conference serves as a platform to share the latest updates, features, and future plans of the app, while also exploring broader topics related to language learning and technology. </p><p>The inaugural Duocon in 2019 featured presentations from Duolingo's team, interactive sessions, and announcements about new developments. The 2020 event was adapted to a virtual format due to the <a href="/wiki/COVID-19_pandemic" title="COVID-19 pandemic">COVID-19 pandemic</a>. Subsequent events have also been held online.<sup id="cite_ref-156" class="reference"><a href="#cite_note-156"><span class="cite-bracket">&#91;</span>152<span class="cite-bracket">&#93;</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Duo's_Taqueria"><span id="Duo.27s_Taqueria"></span>Duo's Taqueria</h2></div> <p><a href="/w/index.php?title=Duo%27s_Taqueria&amp;action=edit&amp;redlink=1" class="new" title="Duo&#39;s Taqueria (page does not exist)">Duo's Taqueria</a> is a <a href="/wiki/Taco_stand" title="Taco stand">taqueria</a> (a Mexican taco restaurant) in Pittsburgh, Pennsylvania, operated by Duolingo. The taqueria offers a variety of authentic Mexican tacos and other traditional dishes.<sup id="cite_ref-157" class="reference"><a href="#cite_note-157"><span class="cite-bracket">&#91;</span>153<span class="cite-bracket">&#93;</span></a></sup> The restaurant encourages patrons to order in Spanish, aligning with Duolingo's mission of making language learning fun and accessible. Duolingo's taco shop brought in $700,000 in 2023.<sup id="cite_ref-158" class="reference"><a href="#cite_note-158"><span class="cite-bracket">&#91;</span>154<span class="cite-bracket">&#93;</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Offices_and_workforce">Offices and workforce</h2></div> <p>Duolingo is headquartered in Pittsburgh, Pennsylvania, and has offices in <a href="/wiki/Seattle" title="Seattle">Seattle</a>, <a href="/wiki/New_York_City" title="New York City">New York</a>,<sup id="cite_ref-fc-5sep2024_159-0" class="reference"><a href="#cite_note-fc-5sep2024-159"><span class="cite-bracket">&#91;</span>155<span class="cite-bracket">&#93;</span></a></sup> <a href="/wiki/Detroit" title="Detroit">Detroit</a>,<sup id="cite_ref-160" class="reference"><a href="#cite_note-160"><span class="cite-bracket">&#91;</span>156<span class="cite-bracket">&#93;</span></a></sup> <a href="/wiki/Beijing" title="Beijing">Beijing</a>, and <a href="/wiki/Berlin" title="Berlin">Berlin</a>.<sup id="cite_ref-161" class="reference"><a href="#cite_note-161"><span class="cite-bracket">&#91;</span>157<span class="cite-bracket">&#93;</span></a></sup> </p><p>In 2024, Duolingo opened a new office in New York City, featuring an art gallery in which the company's characters are depicted in the style of famous historical paintings. The gallery showcases moving images of Duo and other characters in a range of artistic styles.<sup id="cite_ref-162" class="reference"><a href="#cite_note-162"><span class="cite-bracket">&#91;</span>158<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-163" class="reference"><a href="#cite_note-163"><span class="cite-bracket">&#91;</span>159<span class="cite-bracket">&#93;</span></a></sup> </p><p>Duolingo employs around 850 people.<sup id="cite_ref-164" class="reference"><a href="#cite_note-164"><span class="cite-bracket">&#91;</span>160<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-165" class="reference"><a href="#cite_note-165"><span class="cite-bracket">&#91;</span>161<span class="cite-bracket">&#93;</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="See_also">See also</h2></div> <ul><li><a href="/wiki/Distance_education" title="Distance education">Distance education</a></li> <li><a href="/wiki/Language_assessment" title="Language assessment">Language assessment</a></li> <li><a href="/wiki/Language_education" title="Language education">Language education</a></li> <li><a href="/wiki/Language_pedagogy" title="Language pedagogy">Language pedagogy</a></li> <li><a href="/wiki/Mathematics_education" title="Mathematics education">Mathematics education</a></li> <li><a href="/wiki/Music_education" title="Music education">Music education</a></li></ul> <div class="mw-heading mw-heading2"><h2 id="Notes">Notes</h2></div> <style data-mw-deduplicate="TemplateStyles:r1239543626">.mw-parser-output .reflist{margin-bottom:0.5em;list-style-type:decimal}@media screen{.mw-parser-output .reflist{font-size:90%}}.mw-parser-output .reflist .references{font-size:100%;margin-bottom:0;list-style-type:inherit}.mw-parser-output .reflist-columns-2{column-width:30em}.mw-parser-output .reflist-columns-3{column-width:25em}.mw-parser-output .reflist-columns{margin-top:0.3em}.mw-parser-output .reflist-columns ol{margin-top:0}.mw-parser-output .reflist-columns li{page-break-inside:avoid;break-inside:avoid-column}.mw-parser-output .reflist-upper-alpha{list-style-type:upper-alpha}.mw-parser-output .reflist-upper-roman{list-style-type:upper-roman}.mw-parser-output .reflist-lower-alpha{list-style-type:lower-alpha}.mw-parser-output .reflist-lower-greek{list-style-type:lower-greek}.mw-parser-output .reflist-lower-roman{list-style-type:lower-roman}</style><div class="reflist reflist-lower-alpha"> <div class="mw-references-wrap"><ol class="references"> <li id="cite_note-Registration-1"><span class="mw-cite-backlink"><b><a href="#cite_ref-Registration_1-0">^</a></b></span> <span class="reference-text">One can use Duolingo for a few lessons before requiring an account to progress.</span> </li> <li id="cite_note-6"><span class="mw-cite-backlink"><b><a href="#cite_ref-6">^</a></b></span> <span class="reference-text">Pronunciation: <span class="rt-commentedText nowrap"><span class="IPA nopopups noexcerpt" lang="en-fonipa"><a href="/wiki/Help:IPA/English" title="Help:IPA/English">/<span style="border-bottom:1px dotted"><span title="/ˌ/: secondary stress follows">ˌ</span><span title="/dj/: &#39;d&#39; in &#39;dew&#39;">dj</span><span title="/uː/: &#39;oo&#39; in &#39;goose&#39;">uː</span><span title="/oʊ/: &#39;o&#39; in &#39;code&#39;">oʊ</span><span title="/ˈ/: primary stress follows">ˈ</span><span title="&#39;l&#39; in &#39;lie&#39;">l</span><span title="/ɪ/: &#39;i&#39; in &#39;kit&#39;">ɪ</span><span title="/ŋ/: &#39;ng&#39; in &#39;sing&#39;">ŋ</span><span title="/ɡ/: &#39;g&#39; in &#39;guy&#39;">ɡ</span><span title="/oʊ/: &#39;o&#39; in &#39;code&#39;">oʊ</span></span>/</a></span></span> (<a href="/wiki/Help:Pronunciation_respelling_key" title="Help:Pronunciation respelling key"><i title="English pronunciation respelling"><span style="font-size:90%">DEW</span>-oh-<span style="font-size:90%">LING</span>-goh</i></a>)</span> </li> <li id="cite_note-Spanish-67"><span class="mw-cite-backlink">^ <a href="#cite_ref-Spanish_67-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-Spanish_67-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text">For speakers of Spanish</span> </li> <li id="cite_note-Mandarin-68"><span class="mw-cite-backlink"><b><a href="#cite_ref-Mandarin_68-0">^</a></b></span> <span class="reference-text">For speakers of Mandarin Chinese</span> </li> </ol></div></div> <div class="mw-heading mw-heading2"><h2 id="References">References</h2></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239543626"><div class="reflist"> <div class="mw-references-wrap mw-references-columns"><ol class="references"> <li id="cite_note-10K-2"><span class="mw-cite-backlink"><b><a href="#cite_ref-10K_2-0">^</a></b></span> <span class="reference-text"><style data-mw-deduplicate="TemplateStyles:r1238218222">.mw-parser-output cite.citation{font-style:inherit;word-wrap:break-word}.mw-parser-output .citation q{quotes:"\"""\"""'""'"}.mw-parser-output .citation:target{background-color:rgba(0,127,255,0.133)}.mw-parser-output .id-lock-free.id-lock-free a{background:url("//upload.wikimedia.org/wikipedia/commons/6/65/Lock-green.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-limited.id-lock-limited a,.mw-parser-output .id-lock-registration.id-lock-registration a{background:url("//upload.wikimedia.org/wikipedia/commons/d/d6/Lock-gray-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-subscription.id-lock-subscription a{background:url("//upload.wikimedia.org/wikipedia/commons/a/aa/Lock-red-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .cs1-ws-icon a{background:url("//upload.wikimedia.org/wikipedia/commons/4/4c/Wikisource-logo.svg")right 0.1em center/12px no-repeat}body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-free a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-limited a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-registration a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-subscription a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .cs1-ws-icon a{background-size:contain;padding:0 1em 0 0}.mw-parser-output .cs1-code{color:inherit;background:inherit;border:none;padding:inherit}.mw-parser-output .cs1-hidden-error{display:none;color:var(--color-error,#d33)}.mw-parser-output .cs1-visible-error{color:var(--color-error,#d33)}.mw-parser-output .cs1-maint{display:none;color:#085;margin-left:0.3em}.mw-parser-output .cs1-kern-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right{padding-right:0.2em}.mw-parser-output .citation .mw-selflink{font-weight:inherit}@media screen{.mw-parser-output .cs1-format{font-size:95%}html.skin-theme-clientpref-night .mw-parser-output .cs1-maint{color:#18911f}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .cs1-maint{color:#18911f}}</style><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www.sec.gov/ix?doc=/Archives/edgar/data/1562088/000156208824000050/duol-20231231.htm">"Duolingo, Inc. 2023 Annual Report (Form 10-K)"</a>. <a href="/wiki/U.S._Securities_and_Exchange_Commission" title="U.S. Securities and Exchange Commission">U.S. Securities and Exchange Commission</a>. 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April 6, 2020. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20201223023826/https://blog.duolingo.com/migrating-duolingos-android-app-to-100-kotlin/">Archived</a> from the original on December 23, 2020<span class="reference-accessdate">. Retrieved <span class="nowrap">September 17,</span> 2020</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&amp;rft.genre=unknown&amp;rft.jtitle=blog.duolingo.com&amp;rft.atitle=Migrating+Duolingo%27s+Android+app+to+100%25+Kotlin&amp;rft.date=2020-04-06&amp;rft_id=https%3A%2F%2Fblog.duolingo.com%2Fmigrating-duolingos-android-app-to-100-kotlin&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3ADuolingo" class="Z3988"></span></span> </li> <li id="cite_note-real_world_swift-4"><span class="mw-cite-backlink"><b><a href="#cite_ref-real_world_swift_4-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://making.duolingo.com/real-world-swift">"Real World Swift – Making Duolingo Blog"</a>. <i>making.duolingo.com</i>. January 7, 2015. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20190606014131/https://making.duolingo.com/real-world-swift">Archived</a> from the original on June 6, 2019<span class="reference-accessdate">. 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January 31, 2017. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20190804123312/https://making.duolingo.com/rewriting-duolingos-engine-in-scala">Archived</a> from the original on August 4, 2019<span class="reference-accessdate">. Retrieved <span class="nowrap">February 1,</span> 2017</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&amp;rft.genre=unknown&amp;rft.jtitle=making.duolingo.com&amp;rft.atitle=Rewriting+Duolingo%27s+engine+in+Scala+%E2%80%93+Making+Duolingo+Blog&amp;rft.date=2017-01-31&amp;rft_id=http%3A%2F%2Fmaking.duolingo.com%2Frewriting-duolingos-engine-in-scala&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3ADuolingo" class="Z3988"></span></span> </li> <li id="cite_note-7"><span class="mw-cite-backlink"><b><a href="#cite_ref-7">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFOrtiz" class="citation web cs1">Ortiz, Sabrina. <a rel="nofollow" class="external text" href="https://www.zdnet.com/article/duolingo-opens-waitlist-for-its-new-free-music-course-heres-how-to-sign-up/">"Duolingo opens waitlist for its new, free music course. Here's how to sign up"</a>. <i>ZDNET</i>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20231012040140/https://www.zdnet.com/article/duolingo-opens-waitlist-for-its-new-free-music-course-heres-how-to-sign-up/">Archived</a> from the original on October 12, 2023<span class="reference-accessdate">. Retrieved <span class="nowrap">October 11,</span> 2023</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&amp;rft.genre=unknown&amp;rft.jtitle=ZDNET&amp;rft.atitle=Duolingo+opens+waitlist+for+its+new%2C+free+music+course.+Here%27s+how+to+sign+up&amp;rft.aulast=Ortiz&amp;rft.aufirst=Sabrina&amp;rft_id=https%3A%2F%2Fwww.zdnet.com%2Farticle%2Fduolingo-opens-waitlist-for-its-new-free-music-course-heres-how-to-sign-up%2F&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3ADuolingo" class="Z3988"></span></span> </li> <li id="cite_note-math-8"><span class="mw-cite-backlink">^ <a href="#cite_ref-math_8-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-math_8-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFDuolingo_Team2022" class="citation web cs1">Duolingo Team (October 26, 2022). <a rel="nofollow" class="external text" href="https://blog.duolingo.com/duolingo-launches-math-app/">"Duolingo Math makes learning easy as pi(e)"</a>. <i>Duolingo</i>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20221027114012/https://blog.duolingo.com/duolingo-launches-math-app/">Archived</a> from the original on October 27, 2022<span class="reference-accessdate">. Retrieved <span class="nowrap">October 27,</span> 2022</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&amp;rft.genre=unknown&amp;rft.jtitle=Duolingo&amp;rft.atitle=Duolingo+Math+makes+learning+easy+as+pi%28e%29&amp;rft.date=2022-10-26&amp;rft.au=Duolingo+Team&amp;rft_id=https%3A%2F%2Fblog.duolingo.com%2Fduolingo-launches-math-app%2F&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3ADuolingo" class="Z3988"></span></span> </li> <li id="cite_note-:3-9"><span class="mw-cite-backlink">^ <a href="#cite_ref-:3_9-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-:3_9-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFMatt2023" class="citation web cs1">Matt (February 20, 2023). <a rel="nofollow" class="external text" href="https://duoplanet.com/duolingo-languages-list/">"The Complete List Of EVERY Duolingo Language"</a>. <i>Duoplanet</i>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20220921163404/https://duoplanet.com/duolingo-languages-list/">Archived</a> from the original on September 21, 2022<span class="reference-accessdate">. Retrieved <span class="nowrap">September 21,</span> 2022</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&amp;rft.genre=unknown&amp;rft.jtitle=Duoplanet&amp;rft.atitle=The+Complete+List+Of+EVERY+Duolingo+Language&amp;rft.date=2023-02-20&amp;rft.au=Matt&amp;rft_id=https%3A%2F%2Fduoplanet.com%2Fduolingo-languages-list%2F&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3ADuolingo" class="Z3988"></span></span> </li> <li id="cite_note-10"><span class="mw-cite-backlink"><b><a href="#cite_ref-10">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFHiggins-Dunn2019" class="citation web cs1">Higgins-Dunn, Noah (April 14, 2019). <a rel="nofollow" class="external text" href="https://www.cnbc.com/2019/04/14/game-of-thrones-fans-this-app-teaches-you-to-speak-in-high-valyrian.html">"If you are a 'Game of Thrones' fan, this app will teach you how to speak in High Valyrian"</a>. <i><a href="/wiki/CNBC" title="CNBC">CNBC</a></i>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20191112051445/https://www.cnbc.com/2019/04/14/game-of-thrones-fans-this-app-teaches-you-to-speak-in-high-valyrian.html">Archived</a> from the original on November 12, 2019<span class="reference-accessdate">. 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August 26, 2020. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20220518162935/https://blog.duolingo.com/duolingo-abc-unlocking-the-magic-of-reading/">Archived</a> from the original on May 18, 2022<span class="reference-accessdate">. Retrieved <span class="nowrap">May 31,</span> 2022</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&amp;rft.genre=unknown&amp;rft.jtitle=Duolingo+Blog&amp;rft.atitle=Duolingo+ABC%3A+Unlocking+the+magic+of+reading&amp;rft.date=2020-08-26&amp;rft_id=https%3A%2F%2Fblog.duolingo.com%2Fduolingo-abc-unlocking-the-magic-of-reading%2F&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3ADuolingo" class="Z3988"></span></span> </li> <li id="cite_note-85"><span class="mw-cite-backlink"><b><a href="#cite_ref-85">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://store.duolingo.com/collections/accessories/products/loog-x-duolingo-piano">"Loog x Duolingo Piano"</a>. <i>Duolingo Store</i><span class="reference-accessdate">. Retrieved <span class="nowrap">September 25,</span> 2024</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&amp;rft.genre=unknown&amp;rft.jtitle=Duolingo+Store&amp;rft.atitle=Loog+x+Duolingo+Piano&amp;rft_id=https%3A%2F%2Fstore.duolingo.com%2Fcollections%2Faccessories%2Fproducts%2Floog-x-duolingo-piano&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3ADuolingo" class="Z3988"></span></span> </li> <li id="cite_note-86"><span class="mw-cite-backlink"><b><a href="#cite_ref-86">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFLal2024" class="citation web cs1">Lal, Preeti Verma (March 10, 2024). <a rel="nofollow" class="external text" href="https://www.hindustantimes.com/education/study-abroad-all-about-duolingo-english-test-accepted-by-over-5-000-programs-worldwide-101710053253295.html">"Study Abroad: All About Duolingo English Test accepted by over 5,000 programs worldwide"</a>. <i>Hindustan Times</i>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20240606033437/https://www.hindustantimes.com/education/study-abroad-all-about-duolingo-english-test-accepted-by-over-5-000-programs-worldwide-101710053253295.html">Archived</a> from the original on June 6, 2024<span class="reference-accessdate">. Retrieved <span class="nowrap">June 7,</span> 2024</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&amp;rft.genre=unknown&amp;rft.jtitle=Hindustan+Times&amp;rft.atitle=Study+Abroad%3A+All+About+Duolingo+English+Test+accepted+by+over+5%2C000+programs+worldwide&amp;rft.date=2024-03-10&amp;rft.aulast=Lal&amp;rft.aufirst=Preeti+Verma&amp;rft_id=https%3A%2F%2Fwww.hindustantimes.com%2Feducation%2Fstudy-abroad-all-about-duolingo-english-test-accepted-by-over-5-000-programs-worldwide-101710053253295.html&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3ADuolingo" class="Z3988"></span></span> </li> <li id="cite_note-87"><span class="mw-cite-backlink"><b><a href="#cite_ref-87">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFDurrani2023" class="citation web cs1">Durrani, Anayat (December 8, 2023). <a rel="nofollow" class="external text" href="https://www.usnews.com/education/best-global-universities/articles/duolingo-english-test-and-u-s-college-admissions">"Duolingo English Test and U.S. College Admissions"</a>. <i>U.S. News &amp; World Report</i>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20240526041815/https://www.usnews.com/education/best-global-universities/articles/duolingo-english-test-and-u-s-college-admissions">Archived</a> from the original on May 26, 2024<span class="reference-accessdate">. Retrieved <span class="nowrap">June 7,</span> 2024</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&amp;rft.genre=unknown&amp;rft.jtitle=U.S.+News+%26+World+Report&amp;rft.atitle=Duolingo+English+Test+and+U.S.+College+Admissions&amp;rft.date=2023-12-08&amp;rft.aulast=Durrani&amp;rft.aufirst=Anayat&amp;rft_id=https%3A%2F%2Fwww.usnews.com%2Feducation%2Fbest-global-universities%2Farticles%2Fduolingo-english-test-and-u-s-college-admissions&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3ADuolingo" class="Z3988"></span></span> </li> <li id="cite_note-88"><span class="mw-cite-backlink"><b><a href="#cite_ref-88">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFDuolingo2023" class="citation audio-visual cs1">Duolingo (October 11, 2023). <a rel="nofollow" class="external text" href="https://www.youtube.com/watch?v=OVTSGL4BdDU"><i>Introducing The Duolingo Method - How does Duolingo teach new subjects?</i></a><span class="reference-accessdate">. Retrieved <span class="nowrap">August 2,</span> 2024</span> &#8211; via YouTube.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=unknown&amp;rft.btitle=Introducing+The+Duolingo+Method+-+How+does+Duolingo+teach+new+subjects%3F&amp;rft.date=2023-10-11&amp;rft.au=Duolingo&amp;rft_id=https%3A%2F%2Fwww.youtube.com%2Fwatch%3Fv%3DOVTSGL4BdDU&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3ADuolingo" class="Z3988"></span></span> </li> <li id="cite_note-89"><span class="mw-cite-backlink"><b><a href="#cite_ref-89">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFBrockbank2020" class="citation web cs1">Brockbank, Dayna (October 5, 2020). <a rel="nofollow" class="external text" href="https://happilyevertravels.com/duolingo-stories/">"Everything You Need to Know About Duolingo Stories • Happily Ever Travels"</a>. <i>Happily Ever Travels</i>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20211007091457/https://happilyevertravels.com/duolingo-stories/">Archived</a> from the original on October 7, 2021<span class="reference-accessdate">. Retrieved <span class="nowrap">August 26,</span> 2021</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&amp;rft.genre=unknown&amp;rft.jtitle=Happily+Ever+Travels&amp;rft.atitle=Everything+You+Need+to+Know+About+Duolingo+Stories+%E2%80%A2+Happily+Ever+Travels&amp;rft.date=2020-10-05&amp;rft.aulast=Brockbank&amp;rft.aufirst=Dayna&amp;rft_id=https%3A%2F%2Fhappilyevertravels.com%2Fduolingo-stories%2F&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3ADuolingo" class="Z3988"></span></span> </li> <li id="cite_note-90"><span class="mw-cite-backlink"><b><a href="#cite_ref-90">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFPajakTsai2019" class="citation web cs1">Pajak, Bozena; Tsai, Karin (December 11, 2019). <a rel="nofollow" class="external text" href="https://blog.duolingo.com/how-weve-improved-the-duolingo-learning-experience-this-year-and-a-sneak-peek-toward-2020/">"How we've improved the Duolingo learning experience this year (and a sneak peek toward 2020!)"</a>. <i>Duolingo Blog</i>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20210730021026/https://blog.duolingo.com/how-weve-improved-the-duolingo-learning-experience-this-year-and-a-sneak-peek-toward-2020/">Archived</a> from the original on July 30, 2021<span class="reference-accessdate">. Retrieved <span class="nowrap">August 26,</span> 2021</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&amp;rft.genre=unknown&amp;rft.jtitle=Duolingo+Blog&amp;rft.atitle=How+we%27ve+improved+the+Duolingo+learning+experience+this+year+%28and+a+sneak+peek+toward+2020%21%29&amp;rft.date=2019-12-11&amp;rft.aulast=Pajak&amp;rft.aufirst=Bozena&amp;rft.au=Tsai%2C+Karin&amp;rft_id=https%3A%2F%2Fblog.duolingo.com%2Fhow-weve-improved-the-duolingo-learning-experience-this-year-and-a-sneak-peek-toward-2020%2F&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3ADuolingo" class="Z3988"></span></span> </li> <li id="cite_note-91"><span class="mw-cite-backlink"><b><a href="#cite_ref-91">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.tesl-ej.org/pdf/ej73/m1.pdf">"Duolingo"</a> <span class="cs1-format">(PDF)</span>. <i>TESL-EJ</i>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20220122002600/http://www.tesl-ej.org/pdf/ej73/m1.pdf">Archived</a> <span class="cs1-format">(PDF)</span> from the original on January 22, 2022<span class="reference-accessdate">. Retrieved <span class="nowrap">December 31,</span> 2021</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&amp;rft.genre=unknown&amp;rft.jtitle=TESL-EJ&amp;rft.atitle=Duolingo&amp;rft_id=http%3A%2F%2Fwww.tesl-ej.org%2Fpdf%2Fej73%2Fm1.pdf&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3ADuolingo" class="Z3988"></span></span> </li> <li id="cite_note-92"><span class="mw-cite-backlink"><b><a href="#cite_ref-92">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFYanceySettles2020" class="citation book cs1">Yancey, Kevin P.; Settles, Burr (August 20, 2020). <a rel="nofollow" class="external text" href="https://research.duolingo.com/papers/yancey.kdd20.pdf?ref=blog.duolingo.com">"A Sleeping, Recovering Bandit Algorithm for Optimizing Recurring Notifications"</a> <span class="cs1-format">(PDF)</span>. <i>Proceedings of the 26th ACM SIGKDD International Conference on Knowledge Discovery &amp; Data Mining</i>. California, United States: Association for Computing Machinery. pp.&#160;3008–3016. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://doi.org/10.1145%2F3394486.3403351">10.1145/3394486.3403351</a></span>. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a>&#160;<a href="/wiki/Special:BookSources/978-1-4503-7998-4" title="Special:BookSources/978-1-4503-7998-4"><bdi>978-1-4503-7998-4</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=bookitem&amp;rft.atitle=A+Sleeping%2C+Recovering+Bandit+Algorithm+for+Optimizing+Recurring+Notifications&amp;rft.btitle=Proceedings+of+the+26th+ACM+SIGKDD+International+Conference+on+Knowledge+Discovery+%26+Data+Mining&amp;rft.place=California%2C+United+States&amp;rft.pages=3008-3016&amp;rft.pub=Association+for+Computing+Machinery&amp;rft.date=2020-08-20&amp;rft_id=info%3Adoi%2F10.1145%2F3394486.3403351&amp;rft.isbn=978-1-4503-7998-4&amp;rft.aulast=Yancey&amp;rft.aufirst=Kevin+P.&amp;rft.au=Settles%2C+Burr&amp;rft_id=https%3A%2F%2Fresearch.duolingo.com%2Fpapers%2Fyancey.kdd20.pdf%3Fref%3Dblog.duolingo.com&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3ADuolingo" class="Z3988"></span></span> </li> <li id="cite_note-93"><span class="mw-cite-backlink"><b><a href="#cite_ref-93">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFFians2021" class="citation book cs1">Fians, Guilherme (2021). <a rel="nofollow" class="external text" href="https://link.springer.com/book/10.1007/978-3-030-84230-7"><i>Esperanto Revolutionaries and Geeks: Language Politics, Digital Media and the Making of an International Community</i></a>. London and New York: <a href="/wiki/Palgrave_Macmillan" title="Palgrave Macmillan">Palgrave Macmillan</a>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1007%2F978-3-030-84230-7">10.1007/978-3-030-84230-7</a>. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a>&#160;<a href="/wiki/Special:BookSources/978-3-030-84229-1" title="Special:BookSources/978-3-030-84229-1"><bdi>978-3-030-84229-1</bdi></a>. <a href="/wiki/S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a>&#160;<a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:245721938">245721938</a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20221031094243/https://link.springer.com/book/10.1007/978-3-030-84230-7">Archived</a> from the original on October 31, 2022<span class="reference-accessdate">. Retrieved <span class="nowrap">December 2,</span> 2022</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=book&amp;rft.btitle=Esperanto+Revolutionaries+and+Geeks%3A+Language+Politics%2C+Digital+Media+and+the+Making+of+an+International+Community&amp;rft.place=London+and+New+York&amp;rft.pub=Palgrave+Macmillan&amp;rft.date=2021&amp;rft_id=https%3A%2F%2Fapi.semanticscholar.org%2FCorpusID%3A245721938%23id-name%3DS2CID&amp;rft_id=info%3Adoi%2F10.1007%2F978-3-030-84230-7&amp;rft.isbn=978-3-030-84229-1&amp;rft.aulast=Fians&amp;rft.aufirst=Guilherme&amp;rft_id=https%3A%2F%2Flink.springer.com%2Fbook%2F10.1007%2F978-3-030-84230-7&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3ADuolingo" class="Z3988"></span></span> </li> <li id="cite_note-94"><span class="mw-cite-backlink"><b><a href="#cite_ref-94">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFDuolingo_Path2024" class="citation audio-visual cs1">Duolingo Path (September 7, 2024). <a rel="nofollow" class="external text" href="https://www.youtube.com/watch?v=i0YT9VQh4FY"><i>Duolingo Clash</i></a><span class="reference-accessdate">. Retrieved <span class="nowrap">September 8,</span> 2024</span> &#8211; via YouTube.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=unknown&amp;rft.btitle=Duolingo+Clash&amp;rft.date=2024-09-07&amp;rft.au=Duolingo+Path&amp;rft_id=https%3A%2F%2Fwww.youtube.com%2Fwatch%3Fv%3Di0YT9VQh4FY&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3ADuolingo" class="Z3988"></span></span> </li> <li id="cite_note-95"><span class="mw-cite-backlink"><b><a href="#cite_ref-95">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://blog.duolingo.com/avatar-creator/">"Become a Duolingo character with our new Avatars!"</a>. <i>Duolingo Blog</i>. July 19, 2023<span class="reference-accessdate">. Retrieved <span class="nowrap">September 8,</span> 2024</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&amp;rft.genre=unknown&amp;rft.jtitle=Duolingo+Blog&amp;rft.atitle=Become+a+Duolingo+character+with+our+new+Avatars%21&amp;rft.date=2023-07-19&amp;rft_id=https%3A%2F%2Fblog.duolingo.com%2Favatar-creator%2F&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3ADuolingo" class="Z3988"></span></span> </li> <li id="cite_note-96"><span class="mw-cite-backlink"><b><a href="#cite_ref-96">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFHuynhZuoIida2016" class="citation book cs1">Huynh, Duy; Zuo, Long; Iida, Hiroyuki (2016). "Analyzing Gamification of "Duolingo" with Focus on its Course Structure". <i>Games and Learning Alliance</i>. Lecture Notes in Computer Science. Vol.&#160;10056. Springer, Cham. pp.&#160;268–277. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1007%2F978-3-319-50182-6_24">10.1007/978-3-319-50182-6_24</a>. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a>&#160;<a href="/wiki/Special:BookSources/978-3319501819" title="Special:BookSources/978-3319501819"><bdi>978-3319501819</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=bookitem&amp;rft.atitle=Analyzing+Gamification+of+%22Duolingo%22+with+Focus+on+its+Course+Structure&amp;rft.btitle=Games+and+Learning+Alliance&amp;rft.series=Lecture+Notes+in+Computer+Science&amp;rft.pages=268-277&amp;rft.pub=Springer%2C+Cham&amp;rft.date=2016&amp;rft_id=info%3Adoi%2F10.1007%2F978-3-319-50182-6_24&amp;rft.isbn=978-3319501819&amp;rft.aulast=Huynh&amp;rft.aufirst=Duy&amp;rft.au=Zuo%2C+Long&amp;rft.au=Iida%2C+Hiroyuki&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3ADuolingo" class="Z3988"></span></span> </li> <li id="cite_note-97"><span class="mw-cite-backlink"><b><a href="#cite_ref-97">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://blog.duolingo.com/new-subjects/">"Duolingo is bringing language, math, and music under one roof!"</a>. <i>Duolingo Blog</i>. October 11, 2023<span class="reference-accessdate">. Retrieved <span class="nowrap">April 25,</span> 2024</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&amp;rft.genre=unknown&amp;rft.jtitle=Duolingo+Blog&amp;rft.atitle=Duolingo+is+bringing+language%2C+math%2C+and+music+under+one+roof%21&amp;rft.date=2023-10-11&amp;rft_id=https%3A%2F%2Fblog.duolingo.com%2Fnew-subjects%2F&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3ADuolingo" class="Z3988"></span></span> </li> <li id="cite_note-98"><span class="mw-cite-backlink"><b><a href="#cite_ref-98">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://blog.duolingo.com/friend-streak/">"Friend Streak: a new way to stay motivated together"</a>. <i>Duolingo Blog</i>. August 5, 2024<span class="reference-accessdate">. Retrieved <span class="nowrap">September 8,</span> 2024</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&amp;rft.genre=unknown&amp;rft.jtitle=Duolingo+Blog&amp;rft.atitle=Friend+Streak%3A+a+new+way+to+stay+motivated+together&amp;rft.date=2024-08-05&amp;rft_id=https%3A%2F%2Fblog.duolingo.com%2Ffriend-streak%2F&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3ADuolingo" class="Z3988"></span></span> </li> <li id="cite_note-99"><span class="mw-cite-backlink"><b><a href="#cite_ref-99">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://investors.duolingo.com/static-files/d667f9d1-8f7f-418c-b116-e699a30a9826">"Duolingo shareholder letter 2022"</a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20220512201622/https://investors.duolingo.com/static-files/d667f9d1-8f7f-418c-b116-e699a30a9826">Archived</a> from the original on May 12, 2022<span class="reference-accessdate">. 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Retrieved <span class="nowrap">June 6,</span> 2024</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&amp;rft.genre=unknown&amp;rft.jtitle=Duolingo&amp;rft.atitle=Forum+Announcement+%2B+FAQ&amp;rft_id=https%3A%2F%2Fsupport.duolingo.com%2Fhc%2Fen-us%2Farticles%2F4424678300301-Forum-Announcement-FAQ&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3ADuolingo" class="Z3988"></span></span> </li> <li id="cite_note-121"><span class="mw-cite-backlink"><b><a href="#cite_ref-121">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://support.duolingo.com/hc/en-us/articles/204752124-How-do-I-report-a-problem-with-a-sentence-or-translation">"How do I report a problem with a sentence or translation?"</a>. <i>Duolingo</i>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20230923031515/https://support.duolingo.com/hc/en-us/articles/204752124-How-do-I-report-a-problem-with-a-sentence-or-translation-">Archived</a> from the original on September 23, 2023<span class="reference-accessdate">. Retrieved <span class="nowrap">August 12,</span> 2024</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&amp;rft.genre=unknown&amp;rft.jtitle=Duolingo&amp;rft.atitle=How+do+I+report+a+problem+with+a+sentence+or+translation%3F&amp;rft_id=https%3A%2F%2Fsupport.duolingo.com%2Fhc%2Fen-us%2Farticles%2F204752124-How-do-I-report-a-problem-with-a-sentence-or-translation&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3ADuolingo" class="Z3988"></span></span> </li> <li id="cite_note-122"><span class="mw-cite-backlink"><b><a href="#cite_ref-122">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFGreig2023" class="citation web cs1">Greig, Jonathan (January 24, 2023). <a rel="nofollow" class="external text" href="https://therecord.media/duolingo-investigating-dark-web-post-offering-data-from-2-6-million-accounts">"DuoLingo investigating dark web post offering data from 2.6 million accounts"</a>. <i>The Record</i>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20231012025712/https://therecord.media/duolingo-investigating-dark-web-post-offering-data-from-2-6-million-accounts">Archived</a> from the original on October 12, 2023<span class="reference-accessdate">. Retrieved <span class="nowrap">June 6,</span> 2024</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&amp;rft.genre=unknown&amp;rft.jtitle=The+Record&amp;rft.atitle=DuoLingo+investigating+dark+web+post+offering+data+from+2.6+million+accounts&amp;rft.date=2023-01-24&amp;rft.aulast=Greig&amp;rft.aufirst=Jonathan&amp;rft_id=https%3A%2F%2Ftherecord.media%2Fduolingo-investigating-dark-web-post-offering-data-from-2-6-million-accounts&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3ADuolingo" class="Z3988"></span></span> </li> <li id="cite_note-123"><span class="mw-cite-backlink"><b><a href="#cite_ref-123">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFMascellino2023" class="citation web cs1">Mascellino, Alessandro (August 24, 2023). <a rel="nofollow" class="external text" href="https://www.infosecurity-magazine.com/news/data-26m-duolingo-users-leaked/">"Data of 2.6M Duolingo Users Leaked on Hacking Forum"</a>. <i>Infosecurity Magazine</i>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20240221023819/https://www.infosecurity-magazine.com/news/data-26m-duolingo-users-leaked/">Archived</a> from the original on February 21, 2024<span class="reference-accessdate">. Retrieved <span class="nowrap">June 6,</span> 2024</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&amp;rft.genre=unknown&amp;rft.jtitle=Infosecurity+Magazine&amp;rft.atitle=Data+of+2.6M+Duolingo+Users+Leaked+on+Hacking+Forum&amp;rft.date=2023-08-24&amp;rft.aulast=Mascellino&amp;rft.aufirst=Alessandro&amp;rft_id=https%3A%2F%2Fwww.infosecurity-magazine.com%2Fnews%2Fdata-26m-duolingo-users-leaked%2F&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3ADuolingo" class="Z3988"></span></span> </li> <li id="cite_note-124"><span class="mw-cite-backlink"><b><a href="#cite_ref-124">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFNaprys2023" class="citation web cs1">Naprys, Ernestas (November 15, 2023). <a rel="nofollow" class="external text" href="https://cybernews.com/security/hackers-exposed-duolingo-users-more-available-scraping/">"Hackers exposed 2.6 million Duolingo users, more available for scraping"</a>. <i>Cybernews</i>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20240303083615/https://cybernews.com/security/hackers-exposed-duolingo-users-more-available-scraping/">Archived</a> from the original on March 3, 2024<span class="reference-accessdate">. Retrieved <span class="nowrap">June 6,</span> 2024</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&amp;rft.genre=unknown&amp;rft.jtitle=Cybernews&amp;rft.atitle=Hackers+exposed+2.6+million+Duolingo+users%2C+more+available+for+scraping&amp;rft.date=2023-11-15&amp;rft.aulast=Naprys&amp;rft.aufirst=Ernestas&amp;rft_id=https%3A%2F%2Fcybernews.com%2Fsecurity%2Fhackers-exposed-duolingo-users-more-available-scraping%2F&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3ADuolingo" class="Z3988"></span></span> </li> <li id="cite_note-125"><span class="mw-cite-backlink"><b><a href="#cite_ref-125">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFMcCarthyEvans2023" class="citation news cs1">McCarthy, James; Evans, Owain (October 24, 2023). <a rel="nofollow" class="external text" href="https://www.bbc.com/news/uk-wales-67197462">"Welsh course to be 'paused' on language app Duolingo"</a>. 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Retrieved <span class="nowrap">September 7,</span> 2024</span> &#8211; via www.youtube.com.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=unknown&amp;rft.btitle=Inside+Duolingo%27s+Stunning+New+NYC+Office%3A+Art+Gallery+%26+Innovative+Workspaces+Revealed%21&amp;rft_id=https%3A%2F%2Fwww.youtube.com%2Fshorts%2FJCl8xaXOw44&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3ADuolingo" class="Z3988"></span></span> </li> <li id="cite_note-163"><span class="mw-cite-backlink"><b><a href="#cite_ref-163">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFDuolingo_Path2024" class="citation audio-visual cs1">Duolingo Path (September 7, 2024). <a rel="nofollow" class="external text" href="https://www.youtube.com/watch?v=cJJKA1JVY1s"><i>Duolingo Opens New Office in NYC</i></a><span class="reference-accessdate">. Retrieved <span class="nowrap">September 7,</span> 2024</span> &#8211; via YouTube.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=unknown&amp;rft.btitle=Duolingo+Opens+New+Office+in+NYC&amp;rft.date=2024-09-07&amp;rft.au=Duolingo+Path&amp;rft_id=https%3A%2F%2Fwww.youtube.com%2Fwatch%3Fv%3DcJJKA1JVY1s&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3ADuolingo" class="Z3988"></span></span> </li> <li id="cite_note-164"><span class="mw-cite-backlink"><b><a href="#cite_ref-164">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFSeanColombo2024" class="citation web cs1">SeanColombo (September 27, 2024). <a rel="nofollow" class="external text" href="https://www.reddit.com/r/duolingo/comments/1foeq6y/comment/lp71ird/?rdt=63886">"I'm not sure, we don…"</a>. <i>r/duolingo</i><span class="reference-accessdate">. Retrieved <span class="nowrap">September 28,</span> 2024</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&amp;rft.genre=unknown&amp;rft.jtitle=r%2Fduolingo&amp;rft.atitle=I%27m+not+sure%2C+we+don%E2%80%A6&amp;rft.date=2024-09-27&amp;rft.au=SeanColombo&amp;rft_id=https%3A%2F%2Fwww.reddit.com%2Fr%2Fduolingo%2Fcomments%2F1foeq6y%2Fcomment%2Flp71ird%2F%3Frdt%3D63886&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3ADuolingo" class="Z3988"></span></span> </li> <li id="cite_note-165"><span class="mw-cite-backlink"><b><a href="#cite_ref-165">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFPatel2024" class="citation web cs1">Patel, Nilay (October 14, 2024). <a rel="nofollow" class="external text" href="https://www.theverge.com/24267841/luis-von-ahn-duolingo-owl-language-learning-gamification-generative-ai-android-decoder">"Duolingo CEO Luis von Ahn thinks AI has a lot to teach us"</a>. <i>The Verge</i><span class="reference-accessdate">. Retrieved <span class="nowrap">November 2,</span> 2024</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&amp;rft.genre=unknown&amp;rft.jtitle=The+Verge&amp;rft.atitle=Duolingo+CEO+Luis+von+Ahn+thinks+AI+has+a+lot+to+teach+us&amp;rft.date=2024-10-14&amp;rft.aulast=Patel&amp;rft.aufirst=Nilay&amp;rft_id=https%3A%2F%2Fwww.theverge.com%2F24267841%2Fluis-von-ahn-duolingo-owl-language-learning-gamification-generative-ai-android-decoder&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3ADuolingo" class="Z3988"></span></span> </li> </ol></div></div> <div class="mw-heading mw-heading2"><h2 id="External_links">External links</h2></div> <style data-mw-deduplicate="TemplateStyles:r1235681985">.mw-parser-output .side-box{margin:4px 0;box-sizing:border-box;border:1px solid #aaa;font-size:88%;line-height:1.25em;background-color:var(--background-color-interactive-subtle,#f8f9fa);display:flow-root}.mw-parser-output .side-box-abovebelow,.mw-parser-output .side-box-text{padding:0.25em 0.9em}.mw-parser-output .side-box-image{padding:2px 0 2px 0.9em;text-align:center}.mw-parser-output .side-box-imageright{padding:2px 0.9em 2px 0;text-align:center}@media(min-width:500px){.mw-parser-output .side-box-flex{display:flex;align-items:center}.mw-parser-output .side-box-text{flex:1;min-width:0}}@media(min-width:720px){.mw-parser-output .side-box{width:238px}.mw-parser-output .side-box-right{clear:right;float:right;margin-left:1em}.mw-parser-output .side-box-left{margin-right:1em}}</style><style data-mw-deduplicate="TemplateStyles:r1250146164">.mw-parser-output .sister-box .side-box-abovebelow{padding:0.75em 0;text-align:center}.mw-parser-output .sister-box .side-box-abovebelow>b{display:block}.mw-parser-output .sister-box .side-box-text>ul{border-top:1px solid #aaa;padding:0.75em 0;width:217px;margin:0 auto}.mw-parser-output .sister-box .side-box-text>ul>li{min-height:31px}.mw-parser-output .sister-logo{display:inline-block;width:31px;line-height:31px;vertical-align:middle;text-align:center}.mw-parser-output .sister-link{display:inline-block;margin-left:4px;width:182px;vertical-align:middle}@media print{body.ns-0 .mw-parser-output .sistersitebox{display:none!important}}@media screen{html.skin-theme-clientpref-night .mw-parser-output .sistersitebox img[src*="Wiktionary-logo-v2.svg"]{background-color:white}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .sistersitebox img[src*="Wiktionary-logo-v2.svg"]{background-color:white}}</style><div role="navigation" aria-labelledby="sister-projects" class="side-box metadata side-box-right sister-box sistersitebox plainlinks"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1126788409"> <div class="side-box-abovebelow"> <b>Duolingo</b> at Wikipedia's <a href="/wiki/Wikipedia:Wikimedia_sister_projects" title="Wikipedia:Wikimedia sister projects"><span id="sister-projects">sister projects</span></a></div> <div class="side-box-flex"> <div class="side-box-text plainlist"><ul><li><span class="sister-logo"><span class="mw-valign-middle" typeof="mw:File"><span><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/4/4a/Commons-logo.svg/20px-Commons-logo.svg.png" decoding="async" width="20" height="27" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/4/4a/Commons-logo.svg/30px-Commons-logo.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/4/4a/Commons-logo.svg/40px-Commons-logo.svg.png 2x" data-file-width="1024" data-file-height="1376" /></span></span></span><span class="sister-link"><a href="https://commons.wikimedia.org/wiki/Category:Duolingo" class="extiw" title="c:Category:Duolingo">Media</a> from Commons</span></li><li><span class="sister-logo"><span class="mw-valign-middle" typeof="mw:File"><span><img alt="" src="//upload.wikimedia.org/wikipedia/commons/thumb/f/ff/Wikidata-logo.svg/27px-Wikidata-logo.svg.png" decoding="async" width="27" height="15" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/f/ff/Wikidata-logo.svg/41px-Wikidata-logo.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/f/ff/Wikidata-logo.svg/54px-Wikidata-logo.svg.png 2x" data-file-width="1050" data-file-height="590" /></span></span></span><span class="sister-link"><a href="https://www.wikidata.org/wiki/Q2918660" class="extiw" title="d:Q2918660">Data</a> from Wikidata</span></li></ul></div></div> </div> <ul><li><span class="official-website"><span class="url"><a rel="nofollow" class="external text" href="https://en.duolingo.com">Official website</a></span></span> <span class="mw-valign-text-top" typeof="mw:File/Frameless"><a href="https://www.wikidata.org/wiki/Q2918660#P856" title="Edit this at Wikidata"><img alt="Edit this at Wikidata" src="//upload.wikimedia.org/wikipedia/en/thumb/8/8a/OOjs_UI_icon_edit-ltr-progressive.svg/10px-OOjs_UI_icon_edit-ltr-progressive.svg.png" decoding="async" width="10" height="10" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/8/8a/OOjs_UI_icon_edit-ltr-progressive.svg/15px-OOjs_UI_icon_edit-ltr-progressive.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/8/8a/OOjs_UI_icon_edit-ltr-progressive.svg/20px-OOjs_UI_icon_edit-ltr-progressive.svg.png 2x" data-file-width="20" data-file-height="20" /></a></span></li> <li>Business data for Duolingo, Inc.: <style data-mw-deduplicate="TemplateStyles:r1129693374">.mw-parser-output .hlist dl,.mw-parser-output .hlist ol,.mw-parser-output .hlist ul{margin:0;padding:0}.mw-parser-output .hlist dd,.mw-parser-output .hlist dt,.mw-parser-output .hlist li{margin:0;display:inline}.mw-parser-output .hlist.inline,.mw-parser-output .hlist.inline dl,.mw-parser-output .hlist.inline ol,.mw-parser-output .hlist.inline ul,.mw-parser-output .hlist dl dl,.mw-parser-output .hlist dl ol,.mw-parser-output .hlist dl ul,.mw-parser-output .hlist ol dl,.mw-parser-output .hlist ol ol,.mw-parser-output .hlist ol ul,.mw-parser-output .hlist ul dl,.mw-parser-output .hlist ul ol,.mw-parser-output .hlist ul ul{display:inline}.mw-parser-output .hlist .mw-empty-li{display:none}.mw-parser-output .hlist dt::after{content:": "}.mw-parser-output .hlist dd::after,.mw-parser-output .hlist li::after{content:" · ";font-weight:bold}.mw-parser-output .hlist dd:last-child::after,.mw-parser-output .hlist dt:last-child::after,.mw-parser-output .hlist li:last-child::after{content:none}.mw-parser-output .hlist dd dd:first-child::before,.mw-parser-output .hlist dd dt:first-child::before,.mw-parser-output .hlist dd li:first-child::before,.mw-parser-output .hlist dt dd:first-child::before,.mw-parser-output .hlist dt dt:first-child::before,.mw-parser-output .hlist dt li:first-child::before,.mw-parser-output .hlist li dd:first-child::before,.mw-parser-output .hlist li dt:first-child::before,.mw-parser-output .hlist li li:first-child::before{content:" (";font-weight:normal}.mw-parser-output .hlist dd dd:last-child::after,.mw-parser-output .hlist dd dt:last-child::after,.mw-parser-output .hlist dd li:last-child::after,.mw-parser-output .hlist dt dd:last-child::after,.mw-parser-output .hlist dt dt:last-child::after,.mw-parser-output .hlist dt li:last-child::after,.mw-parser-output .hlist li dd:last-child::after,.mw-parser-output .hlist li dt:last-child::after,.mw-parser-output .hlist li li:last-child::after{content:")";font-weight:normal}.mw-parser-output .hlist ol{counter-reset:listitem}.mw-parser-output .hlist ol>li{counter-increment:listitem}.mw-parser-output .hlist ol>li::before{content:" "counter(listitem)"\a0 "}.mw-parser-output .hlist dd ol>li:first-child::before,.mw-parser-output .hlist dt ol>li:first-child::before,.mw-parser-output .hlist li ol>li:first-child::before{content:" ("counter(listitem)"\a0 "}</style><div class="hlist inline"><ul><li><a rel="nofollow" class="external text" href="https://www.bloomberg.com/quote/DUOL:US">Bloomberg</a></li><li><a rel="nofollow" class="external text" href="https://www.google.com/finance/quote/DUOL:NASDAQ">Google</a></li><li><a rel="nofollow" class="external text" href="https://www.reuters.com/markets/companies/DUOL.N">Reuters</a></li><li><a rel="nofollow" class="external text" href="https://www.sec.gov/cgi-bin/browse-edgar?action=getcompany&amp;CIK=1562088">SEC filings</a></li><li><a rel="nofollow" class="external text" href="https://finance.yahoo.com/quote/DUOL">Yahoo!</a></li></ul></div></li></ul> <div class="navbox-styles"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><style data-mw-deduplicate="TemplateStyles:r1236075235">.mw-parser-output .navbox{box-sizing:border-box;border:1px solid #a2a9b1;width:100%;clear:both;font-size:88%;text-align:center;padding:1px;margin:1em auto 0}.mw-parser-output .navbox .navbox{margin-top:0}.mw-parser-output .navbox+.navbox,.mw-parser-output .navbox+.navbox-styles+.navbox{margin-top:-1px}.mw-parser-output .navbox-inner,.mw-parser-output .navbox-subgroup{width:100%}.mw-parser-output .navbox-group,.mw-parser-output .navbox-title,.mw-parser-output .navbox-abovebelow{padding:0.25em 1em;line-height:1.5em;text-align:center}.mw-parser-output .navbox-group{white-space:nowrap;text-align:right}.mw-parser-output .navbox,.mw-parser-output .navbox-subgroup{background-color:#fdfdfd}.mw-parser-output .navbox-list{line-height:1.5em;border-color:#fdfdfd}.mw-parser-output .navbox-list-with-group{text-align:left;border-left-width:2px;border-left-style:solid}.mw-parser-output tr+tr>.navbox-abovebelow,.mw-parser-output tr+tr>.navbox-group,.mw-parser-output tr+tr>.navbox-image,.mw-parser-output tr+tr>.navbox-list{border-top:2px solid #fdfdfd}.mw-parser-output .navbox-title{background-color:#ccf}.mw-parser-output .navbox-abovebelow,.mw-parser-output .navbox-group,.mw-parser-output .navbox-subgroup .navbox-title{background-color:#ddf}.mw-parser-output .navbox-subgroup .navbox-group,.mw-parser-output .navbox-subgroup .navbox-abovebelow{background-color:#e6e6ff}.mw-parser-output .navbox-even{background-color:#f7f7f7}.mw-parser-output .navbox-odd{background-color:transparent}.mw-parser-output .navbox .hlist td dl,.mw-parser-output .navbox .hlist td ol,.mw-parser-output .navbox .hlist td ul,.mw-parser-output .navbox td.hlist dl,.mw-parser-output .navbox td.hlist ol,.mw-parser-output .navbox td.hlist ul{padding:0.125em 0}.mw-parser-output .navbox .navbar{display:block;font-size:100%}.mw-parser-output .navbox-title .navbar{float:left;text-align:left;margin-right:0.5em}body.skin--responsive .mw-parser-output .navbox-image img{max-width:none!important}@media print{body.ns-0 .mw-parser-output .navbox{display:none!important}}</style></div><div role="navigation" class="navbox" aria-labelledby="Duolingo" style="padding:3px"><table class="nowraplinks mw-collapsible expanded navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="col" class="navbox-title" colspan="3"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><style data-mw-deduplicate="TemplateStyles:r1239400231">.mw-parser-output .navbar{display:inline;font-size:88%;font-weight:normal}.mw-parser-output .navbar-collapse{float:left;text-align:left}.mw-parser-output .navbar-boxtext{word-spacing:0}.mw-parser-output .navbar ul{display:inline-block;white-space:nowrap;line-height:inherit}.mw-parser-output .navbar-brackets::before{margin-right:-0.125em;content:"[ "}.mw-parser-output .navbar-brackets::after{margin-left:-0.125em;content:" ]"}.mw-parser-output .navbar li{word-spacing:-0.125em}.mw-parser-output .navbar a>span,.mw-parser-output .navbar a>abbr{text-decoration:inherit}.mw-parser-output .navbar-mini abbr{font-variant:small-caps;border-bottom:none;text-decoration:none;cursor:inherit}.mw-parser-output .navbar-ct-full{font-size:114%;margin:0 7em}.mw-parser-output .navbar-ct-mini{font-size:114%;margin:0 4em}html.skin-theme-clientpref-night .mw-parser-output .navbar li a abbr{color:var(--color-base)!important}@media(prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .navbar li a abbr{color:var(--color-base)!important}}@media print{.mw-parser-output .navbar{display:none!important}}</style><div class="navbar plainlinks hlist navbar-mini"><ul><li class="nv-view"><a href="/wiki/Template:Duolingo" title="Template:Duolingo"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:Duolingo" title="Template talk:Duolingo"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:Duolingo" title="Special:EditPage/Template:Duolingo"><abbr title="Edit this template">e</abbr></a></li></ul></div><div id="Duolingo" style="font-size:114%;margin:0 4em"><a class="mw-selflink selflink">Duolingo</a></div></th></tr><tr><th scope="row" class="navbox-group" style="width:1%">Services</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a class="mw-selflink-fragment" href="#Courses">Language courses</a></li> <li><a class="mw-selflink-fragment" href="#Duolingo_ABC">ABC</a></li> <li><a class="mw-selflink-fragment" href="#Duolingo_Math">Math</a></li> <li><a class="mw-selflink-fragment" href="#Duolingo_Music">Music</a></li> <li><a href="/wiki/Duolingo_English_Test" title="Duolingo English Test">English Test</a></li></ul> </div></td><td class="noviewer navbox-image" rowspan="2" style="width:1px;padding:0 0 0 2px"><div><span typeof="mw:File"><a href="/wiki/File:Duolingo_logo_(2019).svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/5/5c/Duolingo_logo_%282019%29.svg/100px-Duolingo_logo_%282019%29.svg.png" decoding="async" width="100" height="23" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/5/5c/Duolingo_logo_%282019%29.svg/150px-Duolingo_logo_%282019%29.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/5/5c/Duolingo_logo_%282019%29.svg/200px-Duolingo_logo_%282019%29.svg.png 2x" data-file-width="1000" data-file-height="234" /></a></span></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">People</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%">Founders</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Luis_von_Ahn" title="Luis von Ahn">Luis von Ahn</a></li> <li><a href="/wiki/Severin_Hacker" title="Severin Hacker">Severin Hacker</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Key people</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Luis_von_Ahn" title="Luis von Ahn">Luis von Ahn</a> (CEO)</li> <li><a href="/wiki/Severin_Hacker" title="Severin Hacker">Severin Hacker</a> (CTO)</li> <li><a href="/wiki/Cammie_Dunaway" title="Cammie Dunaway">Cammie Dunaway</a> (CMO)</li> <li><a href="/wiki/Linda_Simensky" title="Linda Simensky">Linda Simensky</a> (Head of Animation and Scripted Content)</li> <li><a href="/wiki/Alina_von_Davier" title="Alina von Davier">Alina von Davier</a> (Chief of Assessment)</li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><td class="navbox-abovebelow hlist" colspan="3"><div> <ul><li><span class="noviewer" typeof="mw:File"><span title="Category"><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/16px-Symbol_category_class.svg.png" decoding="async" width="16" height="16" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/23px-Symbol_category_class.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/31px-Symbol_category_class.svg.png 2x" data-file-width="180" data-file-height="185" /></span></span> <a href="/wiki/Category:Duolingo" title="Category:Duolingo">Category</a></li> <li><span class="noviewer" typeof="mw:File"><span title="Commons page"><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/4/4a/Commons-logo.svg/12px-Commons-logo.svg.png" decoding="async" width="12" height="16" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/4/4a/Commons-logo.svg/18px-Commons-logo.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/4/4a/Commons-logo.svg/24px-Commons-logo.svg.png 2x" data-file-width="1024" data-file-height="1376" /></span></span> <a href="https://commons.wikimedia.org/wiki/Category:Duolingo" class="extiw" title="commons:Category:Duolingo">Commons</a></li></ul> </div></td></tr></tbody></table></div> <div class="navbox-styles"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236075235"></div><div role="navigation" class="navbox" aria-labelledby="S&amp;amp;P_400_companies" style="padding:3px"><table class="nowraplinks mw-collapsible autocollapse navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239400231"><div class="navbar plainlinks hlist navbar-mini"><ul><li class="nv-view"><a href="/wiki/Template:S%26P_400_companies" title="Template:S&amp;P 400 companies"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:S%26P_400_companies" title="Template talk:S&amp;P 400 companies"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:S%26P_400_companies" title="Special:EditPage/Template:S&amp;P 400 companies"><abbr title="Edit this template">e</abbr></a></li></ul></div><div id="S&amp;amp;P_400_companies" style="font-size:114%;margin:0 4em"><a href="/wiki/List_of_S%26P_400_companies" title="List of S&amp;P 400 companies">S&amp;P 400 companies</a></div></th></tr><tr><th scope="row" class="navbox-group" style="width:1%">Energy</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Antero_Midstream" class="mw-redirect" title="Antero Midstream">Antero Midstream</a></li> <li><a href="/wiki/Antero_Resources" title="Antero Resources">Antero Resources</a></li> <li><a href="/w/index.php?title=ChampionX&amp;action=edit&amp;redlink=1" class="new" title="ChampionX (page does not exist)">ChampionX</a></li> <li><a href="/wiki/Chord_Energy" title="Chord Energy">Chord Energy</a></li> <li><a href="/w/index.php?title=Civitas_Resources&amp;action=edit&amp;redlink=1" class="new" title="Civitas Resources (page does not exist)">Civitas Resources</a></li> <li><a href="/wiki/CNX_Resources" title="CNX Resources">CNX Resources</a></li> <li><a href="/w/index.php?title=DT_Midstream&amp;action=edit&amp;redlink=1" class="new" title="DT Midstream (page does not exist)">DT Midstream</a></li> <li><a href="/wiki/Expand_Energy" title="Expand Energy">Expand Energy</a></li> <li><a href="/wiki/HF_Sinclair" title="HF Sinclair">HF Sinclair</a></li> <li><a href="/w/index.php?title=Matador_Resources&amp;action=edit&amp;redlink=1" class="new" title="Matador Resources (page does not exist)">Matador Resources</a></li> <li><a href="/wiki/Murphy_Oil" title="Murphy Oil">Murphy Oil</a></li> <li><a href="/wiki/NOV_Inc." title="NOV Inc.">Nov</a></li> <li><a href="/wiki/Ovintiv" title="Ovintiv">Ovintiv</a></li> <li><a href="/wiki/PBF_Energy" title="PBF Energy">PBF Energy</a></li> <li><a href="/w/index.php?title=Permian_Resources&amp;action=edit&amp;redlink=1" class="new" title="Permian Resources (page does not exist)">Permian Resources</a></li> <li><a href="/wiki/Range_Resources" title="Range Resources">Range Resources</a></li> <li><a href="/wiki/Texas_Pacific_Land_Corporation" title="Texas Pacific Land Corporation">Texas Pacific Land Corporation</a></li> <li><a href="/wiki/Valaris_Limited" title="Valaris Limited">Valaris Limited</a></li> <li><a href="/wiki/Weatherford_International" title="Weatherford International">Weatherford International</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Materials</th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Alcoa" title="Alcoa">Alcoa</a></li> <li><a href="/wiki/AptarGroup" title="AptarGroup">AptarGroup</a></li> <li><a href="/wiki/Arcadium_Lithium" title="Arcadium Lithium">Arcadium Lithium</a></li> <li><a href="/wiki/Ashland_Global" title="Ashland Global">Ashland Global</a></li> <li><a href="/wiki/Avient" class="mw-redirect" title="Avient">Avient</a></li> <li><a href="/wiki/Axalta" title="Axalta">Axalta</a></li> <li><a href="/wiki/Berry_Global" title="Berry Global">Berry Global</a></li> <li><a href="/wiki/Cabot_Corp" class="mw-redirect" title="Cabot Corp">Cabot Corp</a></li> <li><a href="/wiki/Chemours" title="Chemours">Chemours</a></li> <li><a href="/wiki/Cleveland-Cliffs" title="Cleveland-Cliffs">Cleveland-Cliffs</a></li> <li><a href="/wiki/Commercial_Metals" class="mw-redirect" title="Commercial Metals">Commercial Metals</a></li> <li><a href="/wiki/Crown_Holdings" title="Crown Holdings">Crown Holdings</a></li> <li><a href="/wiki/Eagle_Materials" title="Eagle Materials">Eagle Materials</a></li> <li><a href="/wiki/Graphic_Packaging" title="Graphic Packaging">Graphic Packaging</a></li> <li><a href="/wiki/Greif,_Inc." title="Greif, Inc.">Greif, Inc.</a></li> <li><a href="/wiki/Knife_River_Corporation" class="mw-redirect" title="Knife River Corporation">Knife River Corporation</a></li> <li><a href="/wiki/Louisiana-Pacific" title="Louisiana-Pacific">Louisiana-Pacific</a></li> <li><a href="/wiki/MP_Materials" title="MP Materials">MP Materials</a></li> <li><a href="/wiki/NewMarket_Corporation" title="NewMarket Corporation">NewMarket Corporation</a></li> <li><a href="/wiki/Olin_Corporation" title="Olin Corporation">Olin</a></li> <li><a href="/wiki/Reliance_Steel_%26_Aluminum_Co." class="mw-redirect" title="Reliance Steel &amp; Aluminum Co.">Reliance Steel &amp; Aluminum Co.</a></li> <li><a href="/wiki/Royal_Gold" title="Royal Gold">Royal Gold</a></li> <li><a href="/wiki/RPM_International" title="RPM International">RPM International</a></li> <li><a href="/wiki/Scotts_Miracle-Gro_Company" title="Scotts Miracle-Gro Company">Scotts Miracle-Gro Company</a></li> <li><a href="/wiki/Silgan_Holdings" title="Silgan Holdings">Silgan Holdings</a></li> <li><a href="/wiki/Sonoco" title="Sonoco">Sonoco</a></li> <li><a href="/wiki/U.S._Steel" title="U.S. Steel">U.S. Steel</a></li> <li><a href="/wiki/Westlake_Corporation" title="Westlake Corporation">Westlake</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Industrials</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Acuity_Brands" title="Acuity Brands">Acuity Brands</a></li> <li><a href="/wiki/Advanced_Drainage_Systems" title="Advanced Drainage Systems">Advanced Drainage Systems</a></li> <li><a href="/wiki/AECOM" title="AECOM">AECOM</a></li> <li><a href="/wiki/AGCO" title="AGCO">AGCO</a></li> <li><a href="/w/index.php?title=ASGN_Inc.&amp;action=edit&amp;redlink=1" class="new" title="ASGN Inc. (page does not exist)">ASGN Inc.</a></li> <li><a href="/wiki/Avis_Budget_Group" title="Avis Budget Group">Avis Budget Group</a></li> <li><a href="/wiki/Brink%27s" title="Brink&#39;s">Brink's</a></li> <li><a href="/wiki/BWX_Technologies" title="BWX Technologies">BWX Technologies</a></li> <li><a href="/wiki/CACI_International" class="mw-redirect" title="CACI International">CACI International</a></li> <li><a href="/wiki/Carlisle_Companies" title="Carlisle Companies">Carlisle Companies</a></li> <li><a href="/w/index.php?title=Chart_Industries&amp;action=edit&amp;redlink=1" class="new" title="Chart Industries (page does not exist)">Chart Industries</a></li> <li><a href="/wiki/Clean_Harbors" title="Clean Harbors">Clean Harbors</a></li> <li><a href="/wiki/Comfort_Systems_USA" title="Comfort Systems USA">Comfort Systems USA</a></li> <li><a href="/wiki/Concentrix" title="Concentrix">Concentrix</a></li> <li><a href="/wiki/Core_%26_Main" title="Core &amp; Main">Core &amp; Main</a></li> <li><a href="/wiki/Crane_Holdings" class="mw-redirect" title="Crane Holdings">Crane</a></li> <li><a href="/wiki/Curtiss-Wright" title="Curtiss-Wright">Curtiss-Wright</a></li> <li><a href="/wiki/Donaldson_Company" title="Donaldson Company">Donaldson</a></li> <li><a href="/wiki/Emcor" title="Emcor">Emcor</a></li> <li><a href="/wiki/EnerSys" title="EnerSys">EnerSys</a></li> <li><a href="/wiki/ESAB" title="ESAB">ESAB</a></li> <li><a href="/wiki/EXL_Service" title="EXL Service">EXL Service</a></li> <li><a href="/wiki/Exponent,_Inc." title="Exponent, Inc.">Exponent, Inc.</a></li> <li><a href="/wiki/Flowserve" title="Flowserve">Flowserve</a></li> <li><a href="/wiki/Fluor_Corporation" title="Fluor Corporation">Fluor</a></li> <li><a href="/wiki/Fortune_Brands_Innovations" title="Fortune Brands Innovations">Fortune Brands Innovations</a></li> <li><a href="/wiki/FTI_Consulting" title="FTI Consulting">FTI Consulting</a></li> <li><a href="/wiki/GATX" title="GATX">GATX</a></li> <li><a href="/wiki/Genpact" title="Genpact">Genpact</a></li> <li><a href="/wiki/Graco_(fluid_handling)" class="mw-redirect" title="Graco (fluid handling)">Graco</a></li> <li><a href="/wiki/GXO_Logistics" title="GXO Logistics">GXO Logistics</a></li> <li><a href="/wiki/Hexcel" title="Hexcel">Hexcel</a></li> <li><a href="/wiki/Insperity" title="Insperity">Insperity</a></li> <li><a href="/wiki/ITT_Inc." title="ITT Inc.">ITT</a></li> <li><a href="/wiki/KBR_(company)" class="mw-redirect" title="KBR (company)">KBR</a></li> <li><a href="/wiki/Kirby_Corporation" title="Kirby Corporation">Kirby</a></li> <li><a href="/wiki/Knight-Swift" title="Knight-Swift">Knight-Swift</a></li> <li><a href="/wiki/Landstar_System" title="Landstar System">Landstar System</a></li> <li><a href="/wiki/Lennox_International" title="Lennox International">Lennox International</a></li> <li><a href="/wiki/Lincoln_Electric" title="Lincoln Electric">Lincoln Electric</a></li> <li><a href="/wiki/ManpowerGroup" title="ManpowerGroup">ManpowerGroup</a></li> <li><a href="/wiki/MasTec" title="MasTec">MasTec</a></li> <li><a href="/wiki/Maximus_Inc." title="Maximus Inc.">Maximus Inc.</a></li> <li><a href="/wiki/Middleby" title="Middleby">Middleby</a></li> <li><a href="/wiki/MSA_Safety" title="MSA Safety">MSA Safety</a></li> <li><a href="/wiki/MSC_Industrial_Direct" title="MSC Industrial Direct">MSC Industrial Direct</a></li> <li><a href="/w/index.php?title=Nextracker&amp;action=edit&amp;redlink=1" class="new" title="Nextracker (page does not exist)">Nextracker</a></li> <li><a href="/w/index.php?title=NVent_Electric_plc&amp;action=edit&amp;redlink=1" class="new" title="NVent Electric plc (page does not exist)">nVent Electric&#160;plc</a></li> <li><a href="/wiki/Oshkosh_Corporation" title="Oshkosh Corporation">Oshkosh</a></li> <li><a href="/wiki/Owens_Corning" title="Owens Corning">Owens Corning</a></li> <li><a href="/wiki/Paylocity" title="Paylocity">Paylocity</a></li> <li><a href="/wiki/RB_Global" title="RB Global">RB Global</a></li> <li><a href="/w/index.php?title=RBC_Bearings&amp;action=edit&amp;redlink=1" class="new" title="RBC Bearings (page does not exist)">RBC Bearings</a></li> <li><a href="/wiki/Regal_Rexnord" title="Regal Rexnord">Regal Rexnord</a></li> <li><a href="/wiki/Ryder" title="Ryder">Ryder</a></li> <li><a href="/wiki/Saia" title="Saia">Saia</a></li> <li><a href="/wiki/Science_Applications_International_Corporation" title="Science Applications International Corporation">Science Applications Intl Corp</a></li> <li><a href="/w/index.php?title=Sensata_Technologies&amp;action=edit&amp;redlink=1" class="new" title="Sensata Technologies (page does not exist)">Sensata Technologies</a></li> <li><a href="/wiki/Simpson_Manufacturing_Company" title="Simpson Manufacturing Company">Simpson Manufacturing Company</a></li> <li><a href="/wiki/Sunrun" title="Sunrun">Sunrun</a></li> <li><a href="/wiki/Terex" title="Terex">Terex</a></li> <li><a href="/wiki/Tetra_Tech" title="Tetra Tech">Tetra Tech</a></li> <li><a href="/wiki/Timken_Company" title="Timken Company">Timken</a></li> <li><a href="/wiki/The_Toro_Company" title="The Toro Company">The Toro Company</a></li> <li><a href="/wiki/Trex_Company,_Inc." title="Trex Company, Inc.">Trex</a></li> <li><a href="/wiki/UFP_Industries" title="UFP Industries">UFP Industries</a></li> <li><a href="/wiki/Valmont_Industries" title="Valmont Industries">Valmont</a></li> <li><a href="/wiki/Watsco" title="Watsco">Watsco</a></li> <li><a href="/w/index.php?title=Watts_Water_Technologies&amp;action=edit&amp;redlink=1" class="new" title="Watts Water Technologies (page does not exist)">Watts Water Technologies</a></li> <li><a href="/wiki/WESCO_International" title="WESCO International">WESCO International</a></li> <li><a href="/wiki/Woodward,_Inc." title="Woodward, Inc.">Woodward</a></li> <li><a href="/wiki/XPO,_Inc." title="XPO, Inc.">XPO, Inc.</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Consumer <br />Discretionary</th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Abercrombie_%26_Fitch" title="Abercrombie &amp; Fitch">Abercrombie &amp; Fitch</a></li> <li><a href="/wiki/Adient" title="Adient">Adient</a></li> <li><a href="/wiki/Aramark" title="Aramark">Aramark</a></li> <li><a href="/wiki/Autoliv" title="Autoliv">Autoliv</a></li> <li><a href="/wiki/AutoNation" title="AutoNation">AutoNation</a></li> <li><a href="/wiki/Boyd_Gaming" title="Boyd Gaming">Boyd Gaming</a></li> <li><a href="/wiki/Brunswick_Corporation" title="Brunswick Corporation">Brunswick</a></li> <li><a href="/wiki/Burlington_(department_store)" title="Burlington (department store)">Burlington</a></li> <li><a href="/wiki/Capri_Holdings" title="Capri Holdings">Capri Holdings</a></li> <li><a href="/wiki/Carter%27s" title="Carter&#39;s">Carter's</a></li> <li><a href="/wiki/Chewy_(company)" title="Chewy (company)">Chewy</a></li> <li><a href="/wiki/Choice_Hotels" title="Choice Hotels">Choice Hotels</a></li> <li><a href="/wiki/Churchill_Downs_Inc." class="mw-redirect" title="Churchill Downs Inc.">Churchill Downs Inc.</a></li> <li><a href="/wiki/Columbia_Sportswear" title="Columbia Sportswear">Columbia Sportswear</a></li> <li><a href="/wiki/Crocs" title="Crocs">Crocs</a></li> <li><a href="/wiki/Deckers_Brands" title="Deckers Brands">Deckers Brands</a></li> <li><a href="/wiki/Dick%27s_Sporting_Goods" title="Dick&#39;s Sporting Goods">Dick's Sporting Goods</a></li> <li><a class="mw-selflink selflink">Duolingo</a></li> <li><a href="/wiki/Five_Below" title="Five Below">Five Below</a></li> <li><a href="/wiki/Floor_%26_Decor" title="Floor &amp; Decor">Floor &amp; Decor</a></li> <li><a href="/wiki/Fox_Factory" title="Fox Factory">Fox Factory</a></li> <li><a href="/wiki/GameStop" title="GameStop">GameStop</a></li> <li><a href="/wiki/Gap_Inc." title="Gap Inc.">Gap</a></li> <li><a href="/wiki/Gentex_(automotive_manufacturer)" class="mw-redirect" title="Gentex (automotive manufacturer)">Gentex</a></li> <li><a href="/wiki/Goodyear_Tire_%26_Rubber" class="mw-redirect" title="Goodyear Tire &amp; Rubber">Goodyear Tire &amp; Rubber</a></li> <li><a href="/wiki/Graham_Holdings" title="Graham Holdings">Graham Holdings</a></li> <li><a href="/wiki/Grand_Canyon_Education" title="Grand Canyon Education">Grand Canyon Education</a></li> <li><a href="/wiki/H%26R_Block" title="H&amp;R Block">H&amp;R Block</a></li> <li><a href="/wiki/Harley-Davidson" title="Harley-Davidson">Harley-Davidson</a></li> <li><a href="/wiki/Helen_of_Troy_Limited" title="Helen of Troy Limited">Helen of Troy Limited</a></li> <li><a href="/wiki/Hilton_Grand_Vacations" title="Hilton Grand Vacations">Hilton Grand Vacations</a></li> <li><a href="/wiki/Hyatt" title="Hyatt">Hyatt</a></li> <li><a href="/wiki/KB_Home" title="KB Home">KB Home</a></li> <li><a href="/wiki/Lear_Corporation" title="Lear 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class="mw-redirect" title="PVH (company)">PVH</a></li> <li><a href="/wiki/RH_(company)" title="RH (company)">RH</a></li> <li><a href="/wiki/Service_Corporation_International" title="Service Corporation International">Service Corp Intl</a></li> <li><a href="/wiki/Skechers" title="Skechers">Skechers</a></li> <li><a href="/wiki/Taylor_Morrison" title="Taylor Morrison">Taylor Morrison</a></li> <li><a href="/wiki/Tempur_Sealy" class="mw-redirect" title="Tempur Sealy">Tempur Sealy</a></li> <li><a href="/wiki/Texas_Roadhouse" title="Texas Roadhouse">Texas Roadhouse</a></li> <li><a href="/wiki/Thor_Industries" title="Thor Industries">Thor Industries</a></li> <li><a href="/wiki/Toll_Brothers" title="Toll Brothers">Toll Brothers</a></li> <li><a href="/w/index.php?title=TopBuild_Corp.&amp;action=edit&amp;redlink=1" class="new" title="TopBuild Corp. (page does not exist)">TopBuild Corp.</a></li> <li><a href="/wiki/Travel_%2B_Leisure_Co." title="Travel + Leisure Co.">Travel + Leisure Co.</a></li> <li><a href="/wiki/Under_Armour" title="Under Armour">Under Armour</a>&#160;(Class A)</li> <li><a href="/wiki/Under_Armour" title="Under Armour">Under Armour</a>&#160;(Class C)</li> <li><a href="/wiki/Vail_Resorts" title="Vail Resorts">Vail Resorts</a></li> <li><a href="/wiki/Valvoline" title="Valvoline">Valvoline</a></li> <li><a href="/wiki/Visteon" title="Visteon">Visteon</a></li> <li><a href="/wiki/Wendy%27s" title="Wendy&#39;s">Wendy's</a></li> <li><a href="/wiki/Williams-Sonoma" class="mw-redirect" title="Williams-Sonoma">Williams-Sonoma</a></li> <li><a href="/wiki/Wingstop" title="Wingstop">Wingstop</a></li> <li><a href="/wiki/Wyndham_Hotels_%26_Resorts" title="Wyndham Hotels &amp; Resorts">Wyndham Hotels &amp; Resorts</a></li> <li><a href="/wiki/Yeti_Holdings" title="Yeti Holdings">Yeti Holdings</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Consumer <br />Staples</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/BellRing_Brands" class="mw-redirect" title="BellRing Brands">BellRing Brands</a></li> <li><a href="/wiki/BJ%27s_Wholesale_Club" title="BJ&#39;s Wholesale Club">BJ's Wholesale Club</a></li> <li><a href="/wiki/Boston_Beer_Company" title="Boston Beer Company">Boston Beer Company</a></li> <li><a href="/wiki/Casey%27s_General_Stores" class="mw-redirect" title="Casey&#39;s General Stores">Casey's General Stores</a></li> <li><a href="/wiki/Celsius_Holdings" title="Celsius Holdings">Celsius Holdings</a></li> <li><a href="/wiki/Coca-Cola_Consolidated" title="Coca-Cola Consolidated">Coca-Cola Consolidated</a></li> <li><a href="/wiki/Coty" title="Coty">Coty</a></li> <li><a href="/w/index.php?title=Darling_Ingredients&amp;action=edit&amp;redlink=1" class="new" title="Darling Ingredients (page does not exist)">Darling Ingredients</a></li> <li><a href="/wiki/E.l.f._(cosmetics)" class="mw-redirect" title="E.l.f. (cosmetics)">e.l.f. Beauty</a></li> <li><a href="/wiki/Flowers_Foods" title="Flowers Foods">Flowers Foods</a></li> <li><a href="/wiki/Ingredion" title="Ingredion">Ingredion</a></li> <li><a href="/w/index.php?title=Lancaster_Colony_Corp&amp;action=edit&amp;redlink=1" class="new" title="Lancaster Colony Corp (page does not exist)">Lancaster Colony Corp</a></li> <li><a href="/wiki/Performance_Food_Group" title="Performance Food Group">Performance Food Group</a></li> <li><a href="/wiki/Pilgrim%27s_Pride" title="Pilgrim&#39;s Pride">Pilgrim's Pride</a></li> <li><a href="/wiki/Post_Holdings" title="Post Holdings">Post Holdings</a></li> <li><a href="/wiki/Sprouts_Farmers_Market" title="Sprouts Farmers Market">Sprouts Farmers Market</a></li> <li><a href="/wiki/US_Foods" title="US Foods">US Foods</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Health Care</th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Acadia_Healthcare" title="Acadia Healthcare">Acadia Healthcare</a></li> <li><a href="/wiki/Amedisys" title="Amedisys">Amedisys</a></li> <li><a href="/wiki/Arrowhead_Pharmaceuticals" title="Arrowhead Pharmaceuticals">Arrowhead Pharmaceuticals</a></li> <li><a href="/wiki/Avantor" title="Avantor">Avantor</a></li> <li><a href="/wiki/BioMarin_Pharmaceutical" title="BioMarin Pharmaceutical">BioMarin Pharmaceutical</a></li> <li><a href="/wiki/Bruker" title="Bruker">Bruker</a></li> <li><a href="/w/index.php?title=Chemed_Corp.&amp;action=edit&amp;redlink=1" class="new" title="Chemed Corp. (page does not exist)">Chemed Corp.</a></li> <li><a href="/wiki/Doximity" title="Doximity">Doximity</a></li> <li><a href="/wiki/Encompass_Health" title="Encompass Health">Encompass Health</a></li> <li><a href="/wiki/Enovis" title="Enovis">Enovis</a></li> <li><a href="/w/index.php?title=Ensign_Group&amp;action=edit&amp;redlink=1" class="new" title="Ensign Group (page does not exist)">Ensign Group</a></li> <li><a href="/w/index.php?title=Envista_Holdings&amp;action=edit&amp;redlink=1" class="new" title="Envista Holdings (page does not exist)">Envista Holdings</a></li> <li><a href="/wiki/Exelixis" title="Exelixis">Exelixis</a></li> <li><a href="/wiki/Globus_Medical" title="Globus Medical">Globus Medical</a></li> <li><a href="/wiki/Haemonetics" title="Haemonetics">Haemonetics</a></li> <li><a href="/wiki/Halozyme" title="Halozyme">Halozyme</a></li> <li><a href="/wiki/HealthEquity" title="HealthEquity">HealthEquity</a></li> <li><a href="/wiki/Illumina,_Inc." title="Illumina, Inc.">Illumina</a></li> <li><a href="/w/index.php?title=Inari_Medical&amp;action=edit&amp;redlink=1" class="new" title="Inari Medical (page does not exist)">Inari Medical</a></li> <li><a href="/wiki/Jazz_Pharmaceuticals" title="Jazz Pharmaceuticals">Jazz Pharmaceuticals</a></li> <li><a href="/wiki/Lantheus_Holdings" title="Lantheus Holdings">Lantheus Holdings</a></li> <li><a href="/wiki/LivaNova" title="LivaNova">LivaNova</a></li> <li><a href="/wiki/Masimo" title="Masimo">Masimo</a></li> <li><a href="/wiki/Medpace" title="Medpace">Medpace</a></li> <li><a href="/wiki/Neogen" title="Neogen">Neogen</a></li> <li><a href="/wiki/Neurocrine_Biosciences" title="Neurocrine Biosciences">Neurocrine Biosciences</a></li> <li><a href="/w/index.php?title=Option_Care_Health&amp;action=edit&amp;redlink=1" class="new" title="Option Care Health (page does not exist)">Option Care Health</a></li> <li><a href="/wiki/Penumbra_(medical_company)" title="Penumbra (medical company)">Penumbra</a></li> <li><a href="/wiki/Perrigo" title="Perrigo">Perrigo</a></li> <li><a href="/w/index.php?title=Progyny&amp;action=edit&amp;redlink=1" class="new" title="Progyny (page does not exist)">Progyny</a></li> <li><a href="/wiki/Repligen" title="Repligen">Repligen</a></li> <li><a href="/w/index.php?title=Shockwave_Medical&amp;action=edit&amp;redlink=1" class="new" title="Shockwave Medical (page does not exist)">Shockwave Medical</a></li> <li><a href="/w/index.php?title=Sotera_Health&amp;action=edit&amp;redlink=1" class="new" title="Sotera Health (page does not exist)">Sotera Health</a></li> <li><a href="/wiki/Tenet_Healthcare" title="Tenet Healthcare">Tenet Healthcare</a></li> <li><a href="/wiki/United_Therapeutics" title="United Therapeutics">United Therapeutics</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Financials</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Affiliated_Managers_Group" title="Affiliated Managers Group">Affiliated Managers Group</a></li> <li><a href="/wiki/Ally_Financial" title="Ally Financial">Ally Financial</a></li> <li><a href="/wiki/American_Financial_Group" title="American Financial Group">American Financial Group</a></li> <li><a href="/wiki/Annaly_Capital_Management" title="Annaly Capital Management">Annaly Capital Management</a></li> <li><a href="/wiki/Associated_Bank" class="mw-redirect" title="Associated Bank">Associated Bank</a></li> <li><a href="/wiki/Bank_OZK" title="Bank OZK">Bank OZK</a></li> <li><a href="/wiki/Brighthouse_Financial" title="Brighthouse Financial">Brighthouse Financial</a></li> <li><a href="/wiki/Cadence_Bank" title="Cadence Bank">Cadence Bank</a></li> <li><a href="/wiki/Carlyle_Group" class="mw-redirect" title="Carlyle Group">Carlyle Group</a></li> <li><a href="/wiki/CNO_Financial_Group" title="CNO Financial Group">CNO Financial Group</a></li> <li><a href="/w/index.php?title=Columbia_Banking_System&amp;action=edit&amp;redlink=1" class="new" title="Columbia Banking System (page does not exist)">Columbia Banking System</a></li> <li><a href="/wiki/Commerce_Bancshares" title="Commerce Bancshares">Commerce Bancshares</a></li> <li><a href="/wiki/East_West_Bancorp" title="East West Bancorp">East West Bancorp</a></li> <li><a href="/wiki/Equitable_Holdings" title="Equitable Holdings">Equitable Holdings</a></li> <li><a href="/wiki/Erie_Indemnity" class="mw-redirect" title="Erie Indemnity">Erie Indemnity</a></li> <li><a href="/w/index.php?title=Essent_Group_Ltd.&amp;action=edit&amp;redlink=1" class="new" title="Essent Group Ltd. (page does not exist)">Essent Group Ltd.</a></li> <li><a href="/wiki/Euronet_Worldwide" title="Euronet Worldwide">Euronet Worldwide</a></li> <li><a href="/wiki/Evercore" title="Evercore">Evercore</a></li> <li><a href="/wiki/Federated_Hermes" title="Federated Hermes">Federated Hermes</a></li> <li><a href="/wiki/Fidelity_National_Financial" title="Fidelity National Financial">Fidelity National Financial</a></li> <li><a href="/wiki/First_American_Corporation" class="mw-redirect" title="First American Corporation">First American</a></li> <li><a href="/w/index.php?title=First_Financial_Bankshares&amp;action=edit&amp;redlink=1" class="new" title="First Financial Bankshares (page does not exist)">First Financial Bankshares</a></li> <li><a href="/wiki/First_Horizon" class="mw-redirect" title="First Horizon">First Horizon</a></li> <li><a href="/wiki/FirstCash" title="FirstCash">FirstCash</a></li> <li><a href="/wiki/FNB_Corporation" title="FNB Corporation">FNB Corporation</a></li> <li><a href="/wiki/Frost_Bank" title="Frost Bank">Frost Bank</a></li> <li><a href="/wiki/Glacier_Bancorp" title="Glacier Bancorp">Glacier Bancorp</a></li> <li><a href="/wiki/Hancock_Whitney" title="Hancock Whitney">Hancock Whitney</a></li> <li><a href="/wiki/Hanover_Insurance" title="Hanover Insurance">Hanover Insurance</a></li> <li><a href="/wiki/Home_BancShares" title="Home BancShares">Home BancShares</a></li> <li><a href="/wiki/Houlihan_Lokey" title="Houlihan Lokey">Houlihan Lokey</a></li> <li><a href="/wiki/Interactive_Brokers" title="Interactive Brokers">Interactive Brokers</a></li> <li><a href="/wiki/International_Bank_of_Commerce" title="International Bank of Commerce">Intl Bancshares Corp</a></li> <li><a href="/wiki/Janus_Henderson" title="Janus Henderson">Janus Henderson</a></li> <li><a href="/wiki/Jefferies_Financial_Group" title="Jefferies Financial Group">Jefferies</a></li> <li><a href="/wiki/Kemper_Corporation" title="Kemper Corporation">Kemper</a></li> <li><a href="/w/index.php?title=Kinsale_Capital_Group&amp;action=edit&amp;redlink=1" class="new" title="Kinsale Capital Group (page does not exist)">Kinsale Capital Group</a></li> <li><a href="/wiki/MGIC_Investment_Corporation" title="MGIC Investment Corporation">MGIC Investment Corporation</a></li> <li><a href="/wiki/Morningstar,_Inc." title="Morningstar, Inc.">Morningstar, Inc.</a></li> <li><a href="/wiki/New_York_Community_Bank" class="mw-redirect" title="New York Community Bank">New York Community Bank</a></li> <li><a href="/wiki/Old_National_Bank" title="Old National Bank">Old National Bank</a></li> <li><a href="/wiki/Old_Republic_International" title="Old Republic International">Old Republic International</a></li> <li><a href="/wiki/Pinnacle_Financial_Partners" title="Pinnacle Financial Partners">Pinnacle Financial Partners</a></li> <li><a href="/wiki/Primerica" title="Primerica">Primerica</a></li> <li><a href="/wiki/Prosperity_Bancshares" title="Prosperity Bancshares">Prosperity Bancshares</a></li> <li><a href="/wiki/Reinsurance_Group_of_America" title="Reinsurance Group of America">Reinsurance Group of America</a></li> <li><a href="/wiki/RenaissanceRe" title="RenaissanceRe">RenaissanceRe</a></li> <li><a href="/wiki/RLI_Corp." title="RLI Corp.">RLI</a></li> <li><a href="/w/index.php?title=Ryan_Specialty&amp;action=edit&amp;redlink=1" class="new" title="Ryan Specialty (page does not exist)">Ryan Specialty</a></li> <li><a href="/wiki/SEI_Investments_Company" title="SEI Investments Company">SEI</a></li> <li><a href="/w/index.php?title=Selective_Insurance_Group&amp;action=edit&amp;redlink=1" class="new" title="Selective Insurance Group (page does not exist)">Selective Insurance Group</a></li> <li><a href="/wiki/Sallie_Mae" title="Sallie Mae">SLM Corp</a></li> <li><a href="/wiki/Shift4" title="Shift4">Shift4</a></li> <li><a href="/wiki/South_State_Bank" class="mw-redirect" title="South State Bank">South State Bank</a></li> <li><a href="/w/index.php?title=Starwood_Property_Trust&amp;action=edit&amp;redlink=1" class="new" title="Starwood Property Trust (page does not exist)">Starwood Property Trust</a></li> <li><a href="/wiki/Stifel" title="Stifel">Stifel</a></li> <li><a href="/wiki/Synovus" title="Synovus">Synovus</a></li> <li><a href="/wiki/Texas_Capital_Bancshares" class="mw-redirect" title="Texas Capital Bancshares">Texas Capital Bancshares</a></li> <li><a href="/wiki/UMB_Financial_Corporation" title="UMB Financial Corporation">UMB Financial Corp.</a></li> <li><a href="/wiki/United_Bankshares" class="mw-redirect" title="United Bankshares">United Bankshares</a></li> <li><a href="/wiki/Unum" title="Unum">Unum</a></li> <li><a href="/wiki/Valley_Bank" title="Valley Bank">Valley Bank</a></li> <li><a href="/wiki/Voya_Financial" title="Voya Financial">Voya Financial</a></li> <li><a href="/wiki/Webster_Bank" title="Webster Bank">Webster Bank</a></li> <li><a href="/wiki/Western_Union" title="Western Union">Western Union</a></li> <li><a href="/wiki/WEX_Inc." title="WEX Inc.">WEX Inc.</a></li> <li><a href="/wiki/Wintrust" class="mw-redirect" title="Wintrust">Wintrust</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Information <br />Technology</th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/w/index.php?title=Allegro_MicroSystems&amp;action=edit&amp;redlink=1" class="new" title="Allegro MicroSystems (page does not exist)">Allegro MicroSystems</a></li> <li><a href="/wiki/Altair_Engineering" title="Altair Engineering">Altair Engineering</a></li> <li><a href="/wiki/Amkor_Technology" title="Amkor Technology">Amkor Technology</a></li> <li><a href="/wiki/Arrow_Electronics" title="Arrow Electronics">Arrow Electronics</a></li> <li><a href="/wiki/Aspen_Technology" title="Aspen Technology">Aspen Technology</a></li> <li><a href="/wiki/Avnet" title="Avnet">Avnet</a></li> <li><a href="/wiki/Belden_(electronics_company)" class="mw-redirect" title="Belden (electronics company)">Belden</a></li> <li><a href="/wiki/Blackbaud" title="Blackbaud">Blackbaud</a></li> <li><a href="/wiki/Calix,_Inc." title="Calix, Inc.">Calix</a></li> <li><a href="/wiki/Ciena" title="Ciena">Ciena</a></li> <li><a href="/wiki/Cirrus_Logic" title="Cirrus Logic">Cirrus Logic</a></li> <li><a href="/wiki/Cognex_Corporation" title="Cognex Corporation">Cognex</a></li> <li><a href="/wiki/Coherent_Corp." title="Coherent Corp.">Coherent Corp.</a></li> <li><a href="/wiki/CommVault_Systems" class="mw-redirect" title="CommVault Systems">CommVault Systems</a></li> <li><a href="/wiki/Crane_Merchandising_Systems" class="mw-redirect" title="Crane Merchandising Systems">Crane NXT</a></li> <li><a href="/wiki/Dolby" title="Dolby">Dolby</a></li> <li><a href="/wiki/Docusign" title="Docusign">Docusign</a></li> <li><a href="/wiki/Dropbox" title="Dropbox">Dropbox</a></li> <li><a href="/wiki/Dynatrace" title="Dynatrace">Dynatrace</a></li> <li><a href="/wiki/Flex_Ltd." title="Flex Ltd.">Flex Ltd.</a></li> <li><a href="/wiki/IPG_Photonics" title="IPG Photonics">IPG Photonics</a></li> <li><a href="/wiki/Kyndryl" title="Kyndryl">Kyndryl</a></li> <li><a href="/wiki/Lattice_Semiconductor" title="Lattice Semiconductor">Lattice Semiconductor</a></li> <li><a href="/wiki/Littelfuse" title="Littelfuse">Littelfuse</a></li> <li><a href="/w/index.php?title=Lumentum_Holdings&amp;action=edit&amp;redlink=1" class="new" title="Lumentum Holdings (page does not exist)">Lumentum Holdings</a></li> <li><a href="/wiki/MACOM_Technology_Solutions" title="MACOM Technology Solutions">MACOM Technology Solutions</a></li> <li><a href="/w/index.php?title=Manhattan_Associates&amp;action=edit&amp;redlink=1" class="new" title="Manhattan Associates (page does not exist)">Manhattan Associates</a></li> <li><a href="/wiki/MKS_Instruments" title="MKS Instruments">MKS Instruments</a></li> <li><a href="/w/index.php?title=Novanta&amp;action=edit&amp;redlink=1" class="new" title="Novanta (page does not exist)">Novanta</a></li> <li><a href="/wiki/Onto_Innovation" title="Onto Innovation">Onto Innovation</a></li> <li><a href="/w/index.php?title=Power_Integrations&amp;action=edit&amp;redlink=1" class="new" title="Power Integrations (page does not exist)">Power Integrations</a></li> <li><a href="/wiki/Pure_Storage" title="Pure Storage">Pure Storage</a></li> <li><a href="/wiki/Qualys" title="Qualys">Qualys</a></li> <li><a href="/wiki/Rambus" title="Rambus">Rambus</a></li> <li><a href="/wiki/Silicon_Labs" title="Silicon Labs">Silicon Labs</a></li> <li><a href="/wiki/Supermicro" title="Supermicro">Supermicro</a></li> <li><a href="/wiki/Synaptics" title="Synaptics">Synaptics</a></li> <li><a href="/wiki/TD_Synnex" title="TD Synnex">TD Synnex</a></li> <li><a href="/wiki/Teradata" title="Teradata">Teradata</a></li> <li><a href="/wiki/Universal_Display_Corporation" title="Universal Display Corporation">Universal Display</a></li> <li><a href="/wiki/Vishay" class="mw-redirect" title="Vishay">Vishay</a></li> <li><a href="/wiki/Vontier" title="Vontier">Vontier</a></li> <li><a href="/wiki/Wolfspeed" title="Wolfspeed">Wolfspeed</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Communication <br />Services</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Frontier_Communications" title="Frontier Communications">Frontier Communications</a></li> <li><a href="/wiki/Iridium_Communications" title="Iridium Communications">Iridium Communications</a></li> <li><a href="/wiki/The_New_York_Times_Company" title="The New York Times Company">The New York Times Company</a></li> <li><a href="/wiki/Nexstar_Media_Group" title="Nexstar Media Group">Nexstar Media Group</a></li> <li><a href="/wiki/Tegna_Inc." title="Tegna Inc.">Tegna</a></li> <li><a href="/wiki/TKO_Group_Holdings" title="TKO Group Holdings">TKO Group Holdings</a></li> <li><a href="/wiki/Warner_Music_Group" title="Warner Music Group">Warner Music Group</a></li> <li><a href="/wiki/Ziff_Davis" title="Ziff Davis">Ziff Davis</a></li> <li><a href="/wiki/ZoomInfo" title="ZoomInfo">ZoomInfo</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Real Estate</th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/w/index.php?title=Agree_Realty&amp;action=edit&amp;redlink=1" class="new" title="Agree Realty (page does not exist)">Agree Realty</a></li> <li><a href="/wiki/Brixmor_Property_Group" title="Brixmor Property Group">Brixmor Property Group</a></li> <li><a href="/wiki/COPT_Defense_Properties" title="COPT Defense Properties">COPT Defense Properties</a></li> <li><a href="/wiki/Cousins_Properties" title="Cousins Properties">Cousins Properties</a></li> <li><a href="/wiki/CubeSmart" title="CubeSmart">CubeSmart</a></li> <li><a href="/w/index.php?title=EastGroup_Properties&amp;action=edit&amp;redlink=1" class="new" title="EastGroup Properties (page does not exist)">EastGroup Properties</a></li> <li><a href="/wiki/EPR_Properties" title="EPR Properties">EPR Properties</a></li> <li><a href="/w/index.php?title=Equity_Lifestyle_Properties&amp;action=edit&amp;redlink=1" class="new" title="Equity Lifestyle Properties (page does not exist)">Equity Lifestyle Properties</a></li> <li><a href="/w/index.php?title=First_Industrial_Realty_Trust&amp;action=edit&amp;redlink=1" class="new" title="First Industrial Realty Trust (page does not exist)">First Industrial Realty Trust</a></li> <li><a href="/wiki/Gaming_and_Leisure_Properties" title="Gaming and Leisure Properties">Gaming and Leisure Properties</a></li> <li><a href="/w/index.php?title=Healthcare_Realty_Trust&amp;action=edit&amp;redlink=1" class="new" title="Healthcare Realty Trust (page does not exist)">Healthcare Realty Trust</a></li> <li><a href="/w/index.php?title=IRT_Living&amp;action=edit&amp;redlink=1" class="new" title="IRT Living (page does not exist)">IRT Living</a></li> <li><a href="/wiki/Jones_Lang_LaSalle" class="mw-redirect" title="Jones Lang LaSalle">Jones Lang LaSalle</a></li> <li><a href="/w/index.php?title=Kilroy_Realty_Corp&amp;action=edit&amp;redlink=1" class="new" title="Kilroy Realty Corp (page does not exist)">Kilroy Realty Corp</a></li> <li><a href="/w/index.php?title=Kite_Realty_Group_Trust&amp;action=edit&amp;redlink=1" class="new" title="Kite Realty Group Trust (page does not exist)">Kite Realty Group Trust</a></li> <li><a href="/wiki/Lamar_Advertising_Company" title="Lamar Advertising Company">Lamar Advertising Company</a></li> <li><a href="/wiki/Medical_Properties_Trust" title="Medical Properties Trust">Medical Properties Trust</a></li> <li><a href="/w/index.php?title=National_Storage_Affiliates_Trust&amp;action=edit&amp;redlink=1" class="new" title="National Storage Affiliates Trust (page does not exist)">National Storage Affiliates Trust</a></li> <li><a href="/wiki/NNN_Reit" title="NNN Reit">NNN Reit</a></li> <li><a href="/w/index.php?title=Omega_Healthcare_Investors&amp;action=edit&amp;redlink=1" class="new" title="Omega Healthcare Investors (page does not exist)">Omega Healthcare Investors</a></li> <li><a href="/wiki/Park_Hotels_%26_Resorts" title="Park Hotels &amp; Resorts">Park Hotels &amp; Resorts</a></li> <li><a href="/w/index.php?title=Physicians_Realty_Trust&amp;action=edit&amp;redlink=1" class="new" title="Physicians Realty Trust (page does not exist)">Physicians Realty Trust</a></li> <li><a href="/wiki/PotlatchDeltic" title="PotlatchDeltic">PotlatchDeltic</a></li> <li><a href="/wiki/Rayonier" title="Rayonier">Rayonier</a></li> <li><a href="/w/index.php?title=Rexford_Industrial_Realty&amp;action=edit&amp;redlink=1" class="new" title="Rexford Industrial Realty (page does not exist)">Rexford Industrial Realty</a></li> <li><a href="/w/index.php?title=Sabra_Health_Care_REIT&amp;action=edit&amp;redlink=1" class="new" title="Sabra Health Care REIT (page does not exist)">Sabra Health Care&#160;REIT</a></li> <li><a href="/w/index.php?title=STAG_Industrial&amp;action=edit&amp;redlink=1" class="new" title="STAG Industrial (page does not exist)">STAG Industrial</a></li> <li><a href="/wiki/Vornado_Realty_Trust" title="Vornado Realty Trust">Vornado Realty Trust</a></li> <li><a href="/wiki/W._P._Carey" title="W. P. Carey">W. P. 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