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Webpage metadata</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Structuring_content/Headings_and_paragraphs">Headings and paragraphs in HTML</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Structuring_content/Emphasis_and_importance">Emphasis and importance</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Structuring_content/Lists">Lists</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Structuring_content/Structuring_documents">Structuring documents</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Structuring_content/Advanced_text_features">Advanced text features</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Structuring_content/Creating_links">Creating links</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Structuring_content/Marking_up_a_letter">Challenge: Marking up a letter</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Structuring_content/Structuring_a_page_of_content">Challenge: Structuring a page of content</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Structuring_content/HTML_images">HTML images</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Structuring_content/HTML_video_and_audio">HTML video and audio</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Structuring_content/Mozilla_splash_page">Challenge: Mozilla splash page</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Structuring_content/HTML_table_basics">HTML table basics</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Structuring_content/Table_accessibility">HTML table accessibility</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Structuring_content/Planet_data_table">Challenge: Structuring a planet data table</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Structuring_content/HTML_forms">Forms and buttons in HTML</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Structuring_content/Debugging_HTML">Debugging HTML</a></li></ol></details></li></ol></details></li><li class="toggle"><details open=""><summary>Guides</summary><ol><li><a href="/en-US/docs/Web/HTML/Content_categories">Content categories</a></li><li><a href="/en-US/docs/Glossary/Block-level_content">Block-level elements</a></li><li><a href="/en-US/docs/Glossary/Inline-level_content">Inline elements</a></li><li><em><a href="/en-US/docs/Web/HTML/Quirks_Mode_and_Standards_Mode" aria-current="page">Quirks Mode and Standards Mode</a></em></li><li><a href="/en-US/docs/Web/HTML/Date_and_time_formats">Date and time formats used in HTML</a></li><li><a href="/en-US/docs/Web/HTML/Constraint_validation">Constraint validation</a></li><li><a href="/en-US/docs/Web/HTML/Microdata">Microdata</a></li><li><a href="/en-US/docs/Web/HTML/microformats">Microformats</a></li><li><a href="/en-US/docs/Web/HTML/Viewport_meta_tag">Viewport meta tag</a></li><li><a href="/en-US/docs/Web/HTML/CORS_enabled_image">Allowing cross-origin use of images and canvas</a></li></ol></details></li><li class="section"><a href="/en-US/docs/Web/HTML/Reference">References</a></li><li class="toggle"><details><summary>HTML elements</summary><ol><li><a href="/en-US/docs/Web/HTML/Element/a"><code><a></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/abbr"><code><abbr></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/acronym"><code><acronym></code></a><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">Deprecated</span> </abbr></li><li><a href="/en-US/docs/Web/HTML/Element/address"><code><address></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/area"><code><area></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/article"><code><article></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/aside"><code><aside></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/audio"><code><audio></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/b"><code><b></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/base"><code><base></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/bdi"><code><bdi></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/bdo"><code><bdo></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/big"><code><big></code></a><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">Deprecated</span> </abbr></li><li><a href="/en-US/docs/Web/HTML/Element/blockquote"><code><blockquote></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/body"><code><body></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/br"><code><br></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/button"><code><button></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/canvas"><code><canvas></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/caption"><code><caption></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/center"><code><center></code></a><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">Deprecated</span> </abbr></li><li><a href="/en-US/docs/Web/HTML/Element/cite"><code><cite></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/code"><code><code></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/col"><code><col></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/colgroup"><code><colgroup></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/data"><code><data></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/datalist"><code><datalist></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/dd"><code><dd></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/del"><code><del></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/details"><code><details></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/dfn"><code><dfn></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/dialog"><code><dialog></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/dir"><code><dir></code></a><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">Deprecated</span> </abbr></li><li><a href="/en-US/docs/Web/HTML/Element/div"><code><div></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/dl"><code><dl></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/dt"><code><dt></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/em"><code><em></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/embed"><code><embed></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/fencedframe"><code><fencedframe></code></a><abbr class="icon icon-experimental" title="Experimental. Expect behavior to change in the future."> <span class="visually-hidden">Experimental</span> </abbr></li><li><a href="/en-US/docs/Web/HTML/Element/fieldset"><code><fieldset></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/figcaption"><code><figcaption></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/figure"><code><figure></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/font"><code><font></code></a><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">Deprecated</span> </abbr></li><li><a href="/en-US/docs/Web/HTML/Element/footer"><code><footer></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/form"><code><form></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/frame"><code><frame></code></a><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">Deprecated</span> </abbr></li><li><a href="/en-US/docs/Web/HTML/Element/frameset"><code><frameset></code></a><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">Deprecated</span> </abbr></li><li><a href="/en-US/docs/Web/HTML/Element/Heading_Elements"><code><h1></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/head"><code><head></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/header"><code><header></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/hgroup"><code><hgroup></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/hr"><code><hr></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/html"><code><html></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/i"><code><i></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/iframe"><code><iframe></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/img"><code><img></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/input"><code><input></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/ins"><code><ins></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/kbd"><code><kbd></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/label"><code><label></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/legend"><code><legend></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/li"><code><li></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/link"><code><link></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/main"><code><main></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/map"><code><map></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/mark"><code><mark></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/marquee"><code><marquee></code></a><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">Deprecated</span> </abbr></li><li><a href="/en-US/docs/Web/HTML/Element/menu"><code><menu></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/meta"><code><meta></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/meter"><code><meter></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/nav"><code><nav></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/nobr"><code><nobr></code></a><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">Deprecated</span> </abbr></li><li><a href="/en-US/docs/Web/HTML/Element/noembed"><code><noembed></code></a><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">Deprecated</span> </abbr></li><li><a href="/en-US/docs/Web/HTML/Element/noframes"><code><noframes></code></a><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">Deprecated</span> </abbr></li><li><a href="/en-US/docs/Web/HTML/Element/noscript"><code><noscript></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/object"><code><object></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/ol"><code><ol></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/optgroup"><code><optgroup></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/option"><code><option></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/output"><code><output></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/p"><code><p></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/param"><code><param></code></a><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">Deprecated</span> </abbr></li><li><a href="/en-US/docs/Web/HTML/Element/picture"><code><picture></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/plaintext"><code><plaintext></code></a><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">Deprecated</span> </abbr></li><li><a href="/en-US/docs/Web/HTML/Element/pre"><code><pre></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/progress"><code><progress></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/q"><code><q></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/rb"><code><rb></code></a><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">Deprecated</span> </abbr></li><li><a href="/en-US/docs/Web/HTML/Element/rp"><code><rp></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/rt"><code><rt></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/rtc"><code><rtc></code></a><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">Deprecated</span> </abbr></li><li><a href="/en-US/docs/Web/HTML/Element/ruby"><code><ruby></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/s"><code><s></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/samp"><code><samp></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/script"><code><script></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/search"><code><search></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/section"><code><section></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/select"><code><select></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/slot"><code><slot></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/small"><code><small></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/source"><code><source></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/span"><code><span></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/strike"><code><strike></code></a><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">Deprecated</span> </abbr></li><li><a href="/en-US/docs/Web/HTML/Element/strong"><code><strong></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/style"><code><style></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/sub"><code><sub></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/summary"><code><summary></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/sup"><code><sup></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/table"><code><table></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/tbody"><code><tbody></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/td"><code><td></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/template"><code><template></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/textarea"><code><textarea></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/tfoot"><code><tfoot></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/th"><code><th></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/thead"><code><thead></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/time"><code><time></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/title"><code><title></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/tr"><code><tr></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/track"><code><track></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/tt"><code><tt></code></a><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">Deprecated</span> </abbr></li><li><a href="/en-US/docs/Web/HTML/Element/u"><code><u></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/ul"><code><ul></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/var"><code><var></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/video"><code><video></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/wbr"><code><wbr></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/xmp"><code><xmp></code></a><abbr class="icon icon-deprecated" title="Deprecated. Not for use in new websites."> <span class="visually-hidden">Deprecated</span> </abbr></li></ol></details></li><li class="toggle"><details><summary>Global attributes</summary><ol><li><a href="/en-US/docs/Web/HTML/Global_attributes/accesskey"><code>accesskey</code></a></li><li><a href="/en-US/docs/Web/HTML/Global_attributes/anchor"><code>anchor</code></a><abbr class="icon icon-experimental" title="Experimental. Expect behavior to change in the future."> <span class="visually-hidden">Experimental</span> </abbr><abbr class="icon icon-nonstandard" title="Non-standard. Check cross-browser support before using."> <span class="visually-hidden">Non-standard</span> </abbr></li><li><a href="/en-US/docs/Web/HTML/Global_attributes/autocapitalize"><code>autocapitalize</code></a></li><li><a href="/en-US/docs/Web/HTML/Global_attributes/autocorrect"><code>autocorrect</code></a></li><li><a href="/en-US/docs/Web/HTML/Global_attributes/autofocus"><code>autofocus</code></a></li><li><a href="/en-US/docs/Web/HTML/Global_attributes/class"><code>class</code></a></li><li><a href="/en-US/docs/Web/HTML/Global_attributes/contenteditable"><code>contenteditable</code></a></li><li><a href="/en-US/docs/Web/HTML/Global_attributes/data-*"><code>data-*</code></a></li><li><a href="/en-US/docs/Web/HTML/Global_attributes/dir"><code>dir</code></a></li><li><a href="/en-US/docs/Web/HTML/Global_attributes/draggable"><code>draggable</code></a></li><li><a href="/en-US/docs/Web/HTML/Global_attributes/enterkeyhint"><code>enterkeyhint</code></a></li><li><a href="/en-US/docs/Web/HTML/Global_attributes/exportparts"><code>exportparts</code></a></li><li><a href="/en-US/docs/Web/HTML/Global_attributes/hidden"><code>hidden</code></a></li><li><a href="/en-US/docs/Web/HTML/Global_attributes/id"><code>id</code></a></li><li><a href="/en-US/docs/Web/HTML/Global_attributes/inert"><code>inert</code></a></li><li><a href="/en-US/docs/Web/HTML/Global_attributes/inputmode"><code>inputmode</code></a></li><li><a href="/en-US/docs/Web/HTML/Global_attributes/is"><code>is</code></a></li><li><a href="/en-US/docs/Web/HTML/Global_attributes/itemid"><code>itemid</code></a></li><li><a href="/en-US/docs/Web/HTML/Global_attributes/itemprop"><code>itemprop</code></a></li><li><a href="/en-US/docs/Web/HTML/Global_attributes/itemref"><code>itemref</code></a></li><li><a href="/en-US/docs/Web/HTML/Global_attributes/itemscope"><code>itemscope</code></a></li><li><a href="/en-US/docs/Web/HTML/Global_attributes/itemtype"><code>itemtype</code></a></li><li><a href="/en-US/docs/Web/HTML/Global_attributes/lang"><code>lang</code></a></li><li><a href="/en-US/docs/Web/HTML/Global_attributes/nonce"><code>nonce</code></a></li><li><a href="/en-US/docs/Web/HTML/Global_attributes/part"><code>part</code></a></li><li><a href="/en-US/docs/Web/HTML/Global_attributes/popover"><code>popover</code></a></li><li><a href="/en-US/docs/Web/HTML/Global_attributes/slot"><code>slot</code></a></li><li><a href="/en-US/docs/Web/HTML/Global_attributes/spellcheck"><code>spellcheck</code></a></li><li><a href="/en-US/docs/Web/HTML/Global_attributes/style"><code>style</code></a></li><li><a href="/en-US/docs/Web/HTML/Global_attributes/tabindex"><code>tabindex</code></a></li><li><a href="/en-US/docs/Web/HTML/Global_attributes/title"><code>title</code></a></li><li><a href="/en-US/docs/Web/HTML/Global_attributes/translate"><code>translate</code></a></li><li><a href="/en-US/docs/Web/HTML/Global_attributes/virtualkeyboardpolicy"><code>virtualkeyboardpolicy</code></a><abbr class="icon icon-experimental" title="Experimental. Expect behavior to change in the future."> <span class="visually-hidden">Experimental</span> </abbr></li><li><a href="/en-US/docs/Web/HTML/Global_attributes/writingsuggestions"><code>writingsuggestions</code></a></li></ol></details></li><li class="toggle"><details><summary>Attributes</summary><ol><li><a href="/en-US/docs/Web/HTML/Attributes/accept">accept</a></li><li><a href="/en-US/docs/Web/HTML/Attributes/autocomplete">autocomplete</a></li><li><a href="/en-US/docs/Web/HTML/Attributes/capture">capture</a></li><li><a href="/en-US/docs/Web/HTML/Attributes/crossorigin">crossorigin</a></li><li><a href="/en-US/docs/Web/HTML/Attributes/dirname">dirname</a></li><li><a href="/en-US/docs/Web/HTML/Attributes/disabled">disabled</a></li><li><a href="/en-US/docs/Web/HTML/Attributes/elementtiming">elementtiming</a></li><li><a href="/en-US/docs/Web/HTML/Attributes/for">for</a></li><li><a href="/en-US/docs/Web/HTML/Attributes/max">max</a></li><li><a href="/en-US/docs/Web/HTML/Attributes/maxlength">maxlength</a></li><li><a href="/en-US/docs/Web/HTML/Attributes/min">min</a></li><li><a href="/en-US/docs/Web/HTML/Attributes/minlength">minlength</a></li><li><a href="/en-US/docs/Web/HTML/Attributes/multiple">multiple</a></li><li><a href="/en-US/docs/Web/HTML/Attributes/pattern">pattern</a></li><li><a href="/en-US/docs/Web/HTML/Attributes/placeholder">placeholder</a></li><li><a href="/en-US/docs/Web/HTML/Attributes/readonly">readonly</a></li><li><a href="/en-US/docs/Web/HTML/Attributes/rel">rel</a></li><li><a href="/en-US/docs/Web/HTML/Attributes/required">required</a></li><li><a href="/en-US/docs/Web/HTML/Attributes/size">size</a></li><li><a href="/en-US/docs/Web/HTML/Attributes/step">step</a></li></ol></details></li><li class="toggle"><details><summary><code><input></code> types</summary><ol><li><a href="/en-US/docs/Web/HTML/Element/input/button"><code><input type="button"></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/input/checkbox"><code><input type="checkbox"></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/input/color"><code><input type="color"></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/input/date"><code><input type="date"></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/input/datetime-local"><code><input type="datetime-local"></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/input/email"><code><input type="email"></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/input/file"><code><input type="file"></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/input/hidden"><code><input type="hidden"></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/input/image"><code><input type="image"></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/input/month"><code><input type="month"></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/input/number"><code><input type="number"></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/input/password"><code><input type="password"></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/input/radio"><code><input type="radio"></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/input/range"><code><input type="range"></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/input/reset"><code><input type="reset"></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/input/search"><code><input type="search"></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/input/submit"><code><input type="submit"></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/input/tel"><code><input type="tel"></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/input/text"><code><input type="text"></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/input/time"><code><input type="time"></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/input/url"><code><input type="url"></code></a></li><li><a href="/en-US/docs/Web/HTML/Element/input/week"><code><input type="week"></code></a></li></ol></details></li></ol></div></div><section class="place side"></section></nav></aside><div class="toc-container"><aside class="toc"><nav><div class="document-toc-container"><section class="document-toc"><header><h2 class="document-toc-heading">In this article</h2></header><ul class="document-toc-list"><li class="document-toc-item "><a class="document-toc-link" href="#how_do_browsers_determine_which_mode_to_use">How do browsers determine which mode to use?</a></li><li class="document-toc-item "><a class="document-toc-link" href="#how_do_i_see_which_mode_is_used">How do I see which mode is used?</a></li></ul></section></div></nav></aside><section class="place side"></section></div></div><main id="content" class="main-content "><article class="main-page-content" lang="en-US"><header><h1>Quirks Mode</h1></header><div class="section-content"><p>In the old days of the web, pages were typically written in two versions: One for Netscape Navigator, and one for Microsoft Internet Explorer. When the web standards were made at W3C, browsers could not just start using them, as doing so would break most existing sites on the web. Browsers therefore introduced two modes to treat new standards compliant sites differently from old legacy sites.</p> <p>There are now three modes used by the layout engines in web browsers: quirks mode, limited-quirks mode, and no-quirks mode. In <strong>quirks mode</strong>, layout emulates behavior in Navigator 4 and Internet Explorer 5. This is essential in order to support websites that were built before the widespread adoption of web standards. In <strong>no-quirks mode</strong>, the behavior is (hopefully) the desired behavior described by the modern HTML and CSS specifications. In <strong>limited-quirks mode</strong>, there are only a very small number of quirks implemented.</p> <p>The limited-quirks and no-quirks modes used to be called "almost-standards" mode and "full standards" mode, respectively. These names have been changed as the behavior is now standardized.</p></div><section aria-labelledby="how_do_browsers_determine_which_mode_to_use"><h2 id="how_do_browsers_determine_which_mode_to_use"><a href="#how_do_browsers_determine_which_mode_to_use">How do browsers determine which mode to use?</a></h2><div class="section-content"><p>For <a href="/en-US/docs/Web/HTML">HTML</a> documents, browsers use a doctype in the beginning of the document to decide whether to handle it in quirks mode or standards mode. To ensure that your page uses full standards mode, make sure that your page has a doctype like in this example:</p> <div class="code-example"><div class="example-header"><span class="language-name">html</span></div><pre class="brush: html notranslate"><code><!doctype html> <html lang="en"> <head> <meta charset="UTF-8" /> <title>Hello World!</title> </head> <body></body> </html> </code></pre></div> <p>The doctype shown in the example, <code><!doctype html></code>, is the simplest possible, and the one recommended by current HTML standards. Earlier versions of the HTML standard recommended other variants, but all existing browsers today will use full standards mode for this doctype. There are no valid reasons to use a more complicated doctype. If you do use another doctype, you may risk choosing one which triggers almost standards mode or quirks mode.</p> <p>Put the doctype right at the beginning of your HTML document, before any other content.</p> <p>The only purpose of <code><!doctype html></code> is to activate no-quirks mode. Older versions of HTML standard doctypes provided additional meaning, but no browser ever used the doctype for anything other than switching between render modes.</p> <p>See also a detailed description of <a href="https://hsivonen.fi/doctype/" class="external" target="_blank">when different browsers choose various modes</a>.</p></div></section><section aria-labelledby="xhtml"><h3 id="xhtml"><a href="#xhtml">XHTML</a></h3><div class="section-content"><p>If you serve your page as <a href="/en-US/docs/Glossary/XHTML">XHTML</a> using the <code>application/xhtml+xml</code> MIME type in the <code>Content-Type</code> HTTP header, you do not need a doctype to enable standards mode, as such documents always use 'full standards mode'.</p> <p>If you serve XHTML-like content using the <code>text/html</code> MIME type, browsers will read it as HTML, and you will need the doctype to use standards mode.</p></div></section><section aria-labelledby="how_do_i_see_which_mode_is_used"><h2 id="how_do_i_see_which_mode_is_used"><a href="#how_do_i_see_which_mode_is_used">How do I see which mode is used?</a></h2><div class="section-content"><p>If the page is rendered in quirks or limited-quirks mode, Firefox will log a warning to the console tab in the developer tools. If this warning is not shown, Firefox is using no-quirks mode.</p> <p>The value of <code>document.compatMode</code> in JavaScript will show whether or not the document is in quirks mode. If its value is <code>"BackCompat"</code>, the document is in quirks mode. If it isn't, it will have value <code>"CSS1Compat"</code>.</p></div></section></article><aside class="article-footer"><div class="article-footer-inner"><div class="svg-container"><svg xmlns="http://www.w3.org/2000/svg" width="162" height="162" viewBox="0 0 162 162" fill="none" role="none"><mask id="b" fill="#fff"><path d="M97.203 47.04c8.113-7.886 18.004-13.871 28.906-17.492a78 78 0 0 1 33.969-3.39c11.443 1.39 22.401 5.295 32.024 11.411s17.656 14.28 23.476 23.86c5.819 9.579 9.269 20.318 10.083 31.385a69.85 69.85 0 0 1-5.387 32.44c-4.358 10.272-11.115 19.443-19.747 26.801-8.632 7.359-18.908 12.709-30.034 15.637l-6.17-21.698c7.666-2.017 14.746-5.703 20.694-10.773 5.948-5.071 10.603-11.389 13.606-18.467a48.14 48.14 0 0 0 3.712-22.352c-.561-7.625-2.938-15.025-6.948-21.625s-9.544-12.226-16.175-16.44-14.181-6.904-22.065-7.863a53.75 53.75 0 0 0-23.405 2.336c-7.513 2.495-14.327 6.62-19.918 12.053z"></path></mask><path stroke="url(#a)" stroke-dasharray="6, 6" stroke-width="2" d="M97.203 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Content available under <a href="/en-US/docs/MDN/Writing_guidelines/Attrib_copyright_license">a Creative Commons license</a>.</p></div></div></footer></div><script type="application/json" id="hydration">{"url":"/en-US/docs/Web/HTML/Quirks_Mode_and_Standards_Mode","doc":{"body":[{"type":"prose","value":{"id":null,"title":null,"isH3":false,"content":"<p>In the old days of the web, pages were typically written in two versions: One for Netscape Navigator, and one for Microsoft Internet Explorer. When the web standards were made at W3C, browsers could not just start using them, as doing so would break most existing sites on the web. Browsers therefore introduced two modes to treat new standards compliant sites differently from old legacy sites.</p>\n<p>There are now three modes used by the layout engines in web browsers: quirks mode, limited-quirks mode, and no-quirks mode. In <strong>quirks mode</strong>, layout emulates behavior in Navigator 4 and Internet Explorer 5. This is essential in order to support websites that were built before the widespread adoption of web standards. In <strong>no-quirks mode</strong>, the behavior is (hopefully) the desired behavior described by the modern HTML and CSS specifications. In <strong>limited-quirks mode</strong>, there are only a very small number of quirks implemented.</p>\n<p>The limited-quirks and no-quirks modes used to be called \"almost-standards\" mode and \"full standards\" mode, respectively. These names have been changed as the behavior is now standardized.</p>"}},{"type":"prose","value":{"id":"how_do_browsers_determine_which_mode_to_use","title":"How do browsers determine which mode to use?","isH3":false,"content":"<p>For <a href=\"/en-US/docs/Web/HTML\">HTML</a> documents, browsers use a doctype in the beginning of the document to decide whether to handle it in quirks mode or standards mode. To ensure that your page uses full standards mode, make sure that your page has a doctype like in this example:</p>\n<div class=\"code-example\"><div class=\"example-header\"><span class=\"language-name\">html</span></div><pre class=\"brush: html notranslate\"><code><!doctype html>\n<html lang=\"en\">\n <head>\n <meta charset=\"UTF-8\" />\n <title>Hello World!</title>\n </head>\n <body></body>\n</html>\n</code></pre></div>\n<p>The doctype shown in the example, <code><!doctype html></code>, is the simplest possible, and the one recommended by current HTML standards. Earlier versions of the HTML standard recommended other variants, but all existing browsers today will use full standards mode for this doctype. There are no valid reasons to use a more complicated doctype. If you do use another doctype, you may risk choosing one which triggers almost standards mode or quirks mode.</p>\n<p>Put the doctype right at the beginning of your HTML document, before any other content.</p>\n<p>The only purpose of <code><!doctype html></code> is to activate no-quirks mode. Older versions of HTML standard doctypes provided additional meaning, but no browser ever used the doctype for anything other than switching between render modes.</p>\n<p>See also a detailed description of <a href=\"https://hsivonen.fi/doctype/\" class=\"external\" target=\"_blank\">when different browsers choose various modes</a>.</p>"}},{"type":"prose","value":{"id":"xhtml","title":"XHTML","isH3":true,"content":"<p>If you serve your page as <a href=\"/en-US/docs/Glossary/XHTML\">XHTML</a> using the <code>application/xhtml+xml</code> MIME type in the <code>Content-Type</code> HTTP header, you do not need a doctype to enable standards mode, as such documents always use 'full standards mode'.</p>\n<p>If you serve XHTML-like content using the <code>text/html</code> MIME type, browsers will read it as HTML, and you will need the doctype to use standards mode.</p>"}},{"type":"prose","value":{"id":"how_do_i_see_which_mode_is_used","title":"How do I see which mode is used?","isH3":false,"content":"<p>If the page is rendered in quirks or limited-quirks mode, Firefox will log a warning to the console tab in the developer tools. If this warning is not shown, Firefox is using no-quirks mode.</p>\n<p>The value of <code>document.compatMode</code> in JavaScript will show whether or not the document is in quirks mode. If its value is <code>\"BackCompat\"</code>, the document is in quirks mode. If it isn't, it will have value <code>\"CSS1Compat\"</code>.</p>"}}],"isActive":true,"isMarkdown":true,"isTranslated":false,"locale":"en-US","mdn_url":"/en-US/docs/Web/HTML/Quirks_Mode_and_Standards_Mode","modified":"2024-09-02T17:10:57.000Z","native":"English (US)","noIndexing":false,"other_translations":[{"locale":"de","title":"Quirks Mode","native":"Deutsch"},{"locale":"es","title":"Modo quirks y modo estándar","native":"Español"},{"locale":"fr","title":"Mode quirks et mode standard","native":"Français"},{"locale":"ja","title":"後方互換モード","native":"日本語"},{"locale":"ko","title":"Quirks 모드","native":"한국어"},{"locale":"pt-BR","title":"Quirks Mode e Standards Mode","native":"Português (do Brasil)"},{"locale":"ru","title":"Режим совместимости (Quirks Mode) и стандартный режим (Standards Mode)","native":"Русский"},{"locale":"zh-CN","title":"怪异模式和标准模式","native":"中文 (简体)"},{"locale":"zh-TW","title":"怪異模式與標準模式","native":"正體中文 (繁體)"}],"pageTitle":"Quirks Mode - HTML: HyperText Markup Language | MDN","parents":[{"uri":"/en-US/docs/Web","title":"References"},{"uri":"/en-US/docs/Web/HTML","title":"HTML"},{"uri":"/en-US/docs/Web/HTML/Quirks_Mode_and_Standards_Mode","title":"Quirks Mode"}],"popularity":null,"short_title":"Quirks Mode","sidebarHTML":"<ol><li class=\"section\"><a href=\"/en-US/docs/Web/HTML\">HTML</a></li><li class=\"toggle\"><details><summary>Beginner's tutorials</summary><ol><li><a href=\"/en-US/docs/Learn_web_development/Getting_started/Your_first_website/Creating_the_content\">Your first website: Creating the content</a></li><li class=\"toggle\"><details><summary><a href=\"/en-US/docs/Learn_web_development/Core/Structuring_content\">Structuring content with HTML</a></summary><ol><li><a href=\"/en-US/docs/Learn_web_development/Core/Structuring_content/Basic_HTML_syntax\">Basic HTML syntax</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Structuring_content/Webpage_metadata\">What's in the head? Webpage metadata</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Structuring_content/Headings_and_paragraphs\">Headings and paragraphs in HTML</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Structuring_content/Emphasis_and_importance\">Emphasis and importance</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Structuring_content/Lists\">Lists</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Structuring_content/Structuring_documents\">Structuring documents</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Structuring_content/Advanced_text_features\">Advanced text features</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Structuring_content/Creating_links\">Creating links</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Structuring_content/Marking_up_a_letter\">Challenge: Marking up a letter</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Structuring_content/Structuring_a_page_of_content\">Challenge: Structuring a page of content</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Structuring_content/HTML_images\">HTML images</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Structuring_content/HTML_video_and_audio\">HTML video and audio</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Structuring_content/Mozilla_splash_page\">Challenge: Mozilla splash page</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Structuring_content/HTML_table_basics\">HTML table basics</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Structuring_content/Table_accessibility\">HTML table accessibility</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Structuring_content/Planet_data_table\">Challenge: Structuring a planet data table</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Structuring_content/HTML_forms\">Forms and buttons in HTML</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Structuring_content/Debugging_HTML\">Debugging HTML</a></li></ol></details></li></ol></details></li><li class=\"toggle\"><details open=\"\"><summary>Guides</summary><ol><li><a href=\"/en-US/docs/Web/HTML/Content_categories\">Content categories</a></li><li><a href=\"/en-US/docs/Glossary/Block-level_content\">Block-level elements</a></li><li><a href=\"/en-US/docs/Glossary/Inline-level_content\">Inline elements</a></li><li><em><a href=\"/en-US/docs/Web/HTML/Quirks_Mode_and_Standards_Mode\" aria-current=\"page\">Quirks Mode and Standards Mode</a></em></li><li><a href=\"/en-US/docs/Web/HTML/Date_and_time_formats\">Date and time formats used in HTML</a></li><li><a href=\"/en-US/docs/Web/HTML/Constraint_validation\">Constraint validation</a></li><li><a href=\"/en-US/docs/Web/HTML/Microdata\">Microdata</a></li><li><a href=\"/en-US/docs/Web/HTML/microformats\">Microformats</a></li><li><a href=\"/en-US/docs/Web/HTML/Viewport_meta_tag\">Viewport meta tag</a></li><li><a href=\"/en-US/docs/Web/HTML/CORS_enabled_image\">Allowing cross-origin use of images and canvas</a></li></ol></details></li><li class=\"section\"><a href=\"/en-US/docs/Web/HTML/Reference\">References</a></li><li class=\"toggle\"><details><summary>HTML elements</summary><ol><li><a href=\"/en-US/docs/Web/HTML/Element/a\"><code><a></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/abbr\"><code><abbr></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/acronym\"><code><acronym></code></a><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n<span class=\"visually-hidden\">Deprecated</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/HTML/Element/address\"><code><address></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/area\"><code><area></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/article\"><code><article></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/aside\"><code><aside></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/audio\"><code><audio></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/b\"><code><b></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/base\"><code><base></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/bdi\"><code><bdi></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/bdo\"><code><bdo></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/big\"><code><big></code></a><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n<span class=\"visually-hidden\">Deprecated</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/HTML/Element/blockquote\"><code><blockquote></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/body\"><code><body></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/br\"><code><br></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/button\"><code><button></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/canvas\"><code><canvas></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/caption\"><code><caption></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/center\"><code><center></code></a><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n<span class=\"visually-hidden\">Deprecated</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/HTML/Element/cite\"><code><cite></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/code\"><code><code></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/col\"><code><col></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/colgroup\"><code><colgroup></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/data\"><code><data></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/datalist\"><code><datalist></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/dd\"><code><dd></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/del\"><code><del></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/details\"><code><details></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/dfn\"><code><dfn></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/dialog\"><code><dialog></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/dir\"><code><dir></code></a><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n<span class=\"visually-hidden\">Deprecated</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/HTML/Element/div\"><code><div></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/dl\"><code><dl></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/dt\"><code><dt></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/em\"><code><em></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/embed\"><code><embed></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/fencedframe\"><code><fencedframe></code></a><abbr class=\"icon icon-experimental\" title=\"Experimental. Expect behavior to change in the future.\">\n<span class=\"visually-hidden\">Experimental</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/HTML/Element/fieldset\"><code><fieldset></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/figcaption\"><code><figcaption></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/figure\"><code><figure></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/font\"><code><font></code></a><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n<span class=\"visually-hidden\">Deprecated</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/HTML/Element/footer\"><code><footer></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/form\"><code><form></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/frame\"><code><frame></code></a><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n<span class=\"visually-hidden\">Deprecated</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/HTML/Element/frameset\"><code><frameset></code></a><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n<span class=\"visually-hidden\">Deprecated</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/HTML/Element/Heading_Elements\"><code><h1></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/head\"><code><head></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/header\"><code><header></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/hgroup\"><code><hgroup></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/hr\"><code><hr></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/html\"><code><html></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/i\"><code><i></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/iframe\"><code><iframe></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/img\"><code><img></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/input\"><code><input></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/ins\"><code><ins></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/kbd\"><code><kbd></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/label\"><code><label></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/legend\"><code><legend></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/li\"><code><li></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/link\"><code><link></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/main\"><code><main></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/map\"><code><map></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/mark\"><code><mark></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/marquee\"><code><marquee></code></a><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n<span class=\"visually-hidden\">Deprecated</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/HTML/Element/menu\"><code><menu></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/meta\"><code><meta></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/meter\"><code><meter></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/nav\"><code><nav></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/nobr\"><code><nobr></code></a><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n<span class=\"visually-hidden\">Deprecated</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/HTML/Element/noembed\"><code><noembed></code></a><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n<span class=\"visually-hidden\">Deprecated</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/HTML/Element/noframes\"><code><noframes></code></a><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n<span class=\"visually-hidden\">Deprecated</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/HTML/Element/noscript\"><code><noscript></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/object\"><code><object></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/ol\"><code><ol></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/optgroup\"><code><optgroup></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/option\"><code><option></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/output\"><code><output></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/p\"><code><p></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/param\"><code><param></code></a><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n<span class=\"visually-hidden\">Deprecated</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/HTML/Element/picture\"><code><picture></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/plaintext\"><code><plaintext></code></a><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n<span class=\"visually-hidden\">Deprecated</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/HTML/Element/pre\"><code><pre></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/progress\"><code><progress></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/q\"><code><q></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/rb\"><code><rb></code></a><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n<span class=\"visually-hidden\">Deprecated</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/HTML/Element/rp\"><code><rp></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/rt\"><code><rt></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/rtc\"><code><rtc></code></a><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n<span class=\"visually-hidden\">Deprecated</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/HTML/Element/ruby\"><code><ruby></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/s\"><code><s></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/samp\"><code><samp></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/script\"><code><script></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/search\"><code><search></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/section\"><code><section></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/select\"><code><select></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/slot\"><code><slot></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/small\"><code><small></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/source\"><code><source></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/span\"><code><span></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/strike\"><code><strike></code></a><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n<span class=\"visually-hidden\">Deprecated</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/HTML/Element/strong\"><code><strong></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/style\"><code><style></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/sub\"><code><sub></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/summary\"><code><summary></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/sup\"><code><sup></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/table\"><code><table></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/tbody\"><code><tbody></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/td\"><code><td></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/template\"><code><template></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/textarea\"><code><textarea></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/tfoot\"><code><tfoot></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/th\"><code><th></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/thead\"><code><thead></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/time\"><code><time></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/title\"><code><title></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/tr\"><code><tr></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/track\"><code><track></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/tt\"><code><tt></code></a><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n<span class=\"visually-hidden\">Deprecated</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/HTML/Element/u\"><code><u></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/ul\"><code><ul></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/var\"><code><var></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/video\"><code><video></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/wbr\"><code><wbr></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/xmp\"><code><xmp></code></a><abbr class=\"icon icon-deprecated\" title=\"Deprecated. Not for use in new websites.\">\n<span class=\"visually-hidden\">Deprecated</span>\n</abbr></li></ol></details></li><li class=\"toggle\"><details><summary>Global attributes</summary><ol><li><a href=\"/en-US/docs/Web/HTML/Global_attributes/accesskey\"><code>accesskey</code></a></li><li><a href=\"/en-US/docs/Web/HTML/Global_attributes/anchor\"><code>anchor</code></a><abbr class=\"icon icon-experimental\" title=\"Experimental. Expect behavior to change in the future.\">\n<span class=\"visually-hidden\">Experimental</span>\n</abbr><abbr class=\"icon icon-nonstandard\" title=\"Non-standard. Check cross-browser support before using.\">\n<span class=\"visually-hidden\">Non-standard</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/HTML/Global_attributes/autocapitalize\"><code>autocapitalize</code></a></li><li><a href=\"/en-US/docs/Web/HTML/Global_attributes/autocorrect\"><code>autocorrect</code></a></li><li><a href=\"/en-US/docs/Web/HTML/Global_attributes/autofocus\"><code>autofocus</code></a></li><li><a href=\"/en-US/docs/Web/HTML/Global_attributes/class\"><code>class</code></a></li><li><a href=\"/en-US/docs/Web/HTML/Global_attributes/contenteditable\"><code>contenteditable</code></a></li><li><a href=\"/en-US/docs/Web/HTML/Global_attributes/data-*\"><code>data-*</code></a></li><li><a href=\"/en-US/docs/Web/HTML/Global_attributes/dir\"><code>dir</code></a></li><li><a href=\"/en-US/docs/Web/HTML/Global_attributes/draggable\"><code>draggable</code></a></li><li><a href=\"/en-US/docs/Web/HTML/Global_attributes/enterkeyhint\"><code>enterkeyhint</code></a></li><li><a href=\"/en-US/docs/Web/HTML/Global_attributes/exportparts\"><code>exportparts</code></a></li><li><a href=\"/en-US/docs/Web/HTML/Global_attributes/hidden\"><code>hidden</code></a></li><li><a href=\"/en-US/docs/Web/HTML/Global_attributes/id\"><code>id</code></a></li><li><a href=\"/en-US/docs/Web/HTML/Global_attributes/inert\"><code>inert</code></a></li><li><a href=\"/en-US/docs/Web/HTML/Global_attributes/inputmode\"><code>inputmode</code></a></li><li><a href=\"/en-US/docs/Web/HTML/Global_attributes/is\"><code>is</code></a></li><li><a href=\"/en-US/docs/Web/HTML/Global_attributes/itemid\"><code>itemid</code></a></li><li><a href=\"/en-US/docs/Web/HTML/Global_attributes/itemprop\"><code>itemprop</code></a></li><li><a href=\"/en-US/docs/Web/HTML/Global_attributes/itemref\"><code>itemref</code></a></li><li><a href=\"/en-US/docs/Web/HTML/Global_attributes/itemscope\"><code>itemscope</code></a></li><li><a href=\"/en-US/docs/Web/HTML/Global_attributes/itemtype\"><code>itemtype</code></a></li><li><a href=\"/en-US/docs/Web/HTML/Global_attributes/lang\"><code>lang</code></a></li><li><a href=\"/en-US/docs/Web/HTML/Global_attributes/nonce\"><code>nonce</code></a></li><li><a href=\"/en-US/docs/Web/HTML/Global_attributes/part\"><code>part</code></a></li><li><a href=\"/en-US/docs/Web/HTML/Global_attributes/popover\"><code>popover</code></a></li><li><a href=\"/en-US/docs/Web/HTML/Global_attributes/slot\"><code>slot</code></a></li><li><a href=\"/en-US/docs/Web/HTML/Global_attributes/spellcheck\"><code>spellcheck</code></a></li><li><a href=\"/en-US/docs/Web/HTML/Global_attributes/style\"><code>style</code></a></li><li><a href=\"/en-US/docs/Web/HTML/Global_attributes/tabindex\"><code>tabindex</code></a></li><li><a href=\"/en-US/docs/Web/HTML/Global_attributes/title\"><code>title</code></a></li><li><a href=\"/en-US/docs/Web/HTML/Global_attributes/translate\"><code>translate</code></a></li><li><a href=\"/en-US/docs/Web/HTML/Global_attributes/virtualkeyboardpolicy\"><code>virtualkeyboardpolicy</code></a><abbr class=\"icon icon-experimental\" title=\"Experimental. Expect behavior to change in the future.\">\n<span class=\"visually-hidden\">Experimental</span>\n</abbr></li><li><a href=\"/en-US/docs/Web/HTML/Global_attributes/writingsuggestions\"><code>writingsuggestions</code></a></li></ol></details></li><li class=\"toggle\"><details><summary>Attributes</summary><ol><li><a href=\"/en-US/docs/Web/HTML/Attributes/accept\">accept</a></li><li><a href=\"/en-US/docs/Web/HTML/Attributes/autocomplete\">autocomplete</a></li><li><a href=\"/en-US/docs/Web/HTML/Attributes/capture\">capture</a></li><li><a href=\"/en-US/docs/Web/HTML/Attributes/crossorigin\">crossorigin</a></li><li><a href=\"/en-US/docs/Web/HTML/Attributes/dirname\">dirname</a></li><li><a href=\"/en-US/docs/Web/HTML/Attributes/disabled\">disabled</a></li><li><a href=\"/en-US/docs/Web/HTML/Attributes/elementtiming\">elementtiming</a></li><li><a href=\"/en-US/docs/Web/HTML/Attributes/for\">for</a></li><li><a href=\"/en-US/docs/Web/HTML/Attributes/max\">max</a></li><li><a href=\"/en-US/docs/Web/HTML/Attributes/maxlength\">maxlength</a></li><li><a href=\"/en-US/docs/Web/HTML/Attributes/min\">min</a></li><li><a href=\"/en-US/docs/Web/HTML/Attributes/minlength\">minlength</a></li><li><a href=\"/en-US/docs/Web/HTML/Attributes/multiple\">multiple</a></li><li><a href=\"/en-US/docs/Web/HTML/Attributes/pattern\">pattern</a></li><li><a href=\"/en-US/docs/Web/HTML/Attributes/placeholder\">placeholder</a></li><li><a href=\"/en-US/docs/Web/HTML/Attributes/readonly\">readonly</a></li><li><a href=\"/en-US/docs/Web/HTML/Attributes/rel\">rel</a></li><li><a href=\"/en-US/docs/Web/HTML/Attributes/required\">required</a></li><li><a href=\"/en-US/docs/Web/HTML/Attributes/size\">size</a></li><li><a href=\"/en-US/docs/Web/HTML/Attributes/step\">step</a></li></ol></details></li><li class=\"toggle\"><details><summary><code><input></code> types</summary><ol><li><a href=\"/en-US/docs/Web/HTML/Element/input/button\"><code><input type=\"button\"></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/input/checkbox\"><code><input type=\"checkbox\"></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/input/color\"><code><input type=\"color\"></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/input/date\"><code><input type=\"date\"></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/input/datetime-local\"><code><input type=\"datetime-local\"></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/input/email\"><code><input type=\"email\"></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/input/file\"><code><input type=\"file\"></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/input/hidden\"><code><input type=\"hidden\"></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/input/image\"><code><input type=\"image\"></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/input/month\"><code><input type=\"month\"></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/input/number\"><code><input type=\"number\"></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/input/password\"><code><input type=\"password\"></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/input/radio\"><code><input type=\"radio\"></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/input/range\"><code><input type=\"range\"></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/input/reset\"><code><input type=\"reset\"></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/input/search\"><code><input type=\"search\"></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/input/submit\"><code><input type=\"submit\"></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/input/tel\"><code><input type=\"tel\"></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/input/text\"><code><input type=\"text\"></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/input/time\"><code><input type=\"time\"></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/input/url\"><code><input type=\"url\"></code></a></li><li><a href=\"/en-US/docs/Web/HTML/Element/input/week\"><code><input type=\"week\"></code></a></li></ol></details></li></ol>","source":{"folder":"en-us/web/html/quirks_mode_and_standards_mode","github_url":"https://github.com/mdn/content/blob/main/files/en-us/web/html/quirks_mode_and_standards_mode/index.md","last_commit_url":"https://github.com/mdn/content/commit/88467d31d2ad7bdfade8b38ec69f6702fee080d1","filename":"index.md"},"summary":"In the old days of the web, pages were typically written in two versions: One for Netscape Navigator, and one for Microsoft Internet Explorer. When the web standards were made at W3C, browsers could not just start using them, as doing so would break most existing sites on the web. Browsers therefore introduced two modes to treat new standards compliant sites differently from old legacy sites.","title":"Quirks Mode","toc":[{"text":"How do browsers determine which mode to use?","id":"how_do_browsers_determine_which_mode_to_use"},{"text":"How do I see which mode is used?","id":"how_do_i_see_which_mode_is_used"}],"pageType":"guide"}}</script></body></html>