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vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Algorithms"> <div class="vector-toc-text"> <span class="vector-toc-numb">2</span> <span>Algorithms</span> </div> </a> <ul id="toc-Algorithms-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Perpetual_Julian_and_Gregorian_calendar_tables" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Perpetual_Julian_and_Gregorian_calendar_tables"> <div class="vector-toc-text"> <span class="vector-toc-numb">3</span> <span>Perpetual Julian and Gregorian calendar tables</span> </div> </a> <button aria-controls="toc-Perpetual_Julian_and_Gregorian_calendar_tables-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 Perpetual Julian and Gregorian calendar tables subsection</span> </button> <ul id="toc-Perpetual_Julian_and_Gregorian_calendar_tables-sublist" class="vector-toc-list"> <li id="toc-Table_one_(cyd)" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Table_one_(cyd)"> <div class="vector-toc-text"> <span class="vector-toc-numb">3.1</span> <span>Table one (cyd)</span> </div> </a> <ul id="toc-Table_one_(cyd)-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Table_two_(cymd)" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Table_two_(cymd)"> <div class="vector-toc-text"> <span class="vector-toc-numb">3.2</span> <span>Table two (cymd)</span> </div> </a> <ul id="toc-Table_two_(cymd)-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Table_three_(dmyc)" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Table_three_(dmyc)"> <div class="vector-toc-text"> <span class="vector-toc-numb">3.3</span> <span>Table three (dmyc)</span> </div> </a> <ul id="toc-Table_three_(dmyc)-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-See_also" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#See_also"> <div class="vector-toc-text"> <span class="vector-toc-numb">4</span> <span>See also</span> </div> </a> <ul id="toc-See_also-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-References" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#References"> <div class="vector-toc-text"> <span class="vector-toc-numb">5</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 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#External_links"> <div class="vector-toc-text"> <span class="vector-toc-numb">6</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 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Available in 19 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-19" 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">19 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%AA%D9%82%D9%88%D9%8A%D9%85_%D8%AF%D8%A7%D8%A6%D9%85" title="تقويم دائم – Arabic" lang="ar" hreflang="ar" data-title="تقويم دائم" data-language-autonym="العربية" data-language-local-name="Arabic" class="interlanguage-link-target"><span>العربية</span></a></li><li class="interlanguage-link interwiki-ca mw-list-item"><a href="https://ca.wikipedia.org/wiki/Calendari_perpetu" title="Calendari perpetu – Catalan" lang="ca" hreflang="ca" data-title="Calendari perpetu" data-language-autonym="Català" data-language-local-name="Catalan" class="interlanguage-link-target"><span>Català</span></a></li><li class="interlanguage-link interwiki-de mw-list-item"><a href="https://de.wikipedia.org/wiki/Ewiger_Kalender" title="Ewiger Kalender – German" lang="de" hreflang="de" data-title="Ewiger Kalender" data-language-autonym="Deutsch" data-language-local-name="German" class="interlanguage-link-target"><span>Deutsch</span></a></li><li class="interlanguage-link interwiki-es mw-list-item"><a href="https://es.wikipedia.org/wiki/Calendario_perpetuo" title="Calendario perpetuo – Spanish" lang="es" hreflang="es" data-title="Calendario perpetuo" data-language-autonym="Español" data-language-local-name="Spanish" class="interlanguage-link-target"><span>Español</span></a></li><li class="interlanguage-link interwiki-eu mw-list-item"><a href="https://eu.wikipedia.org/wiki/Betiereko_egutegi" title="Betiereko egutegi – Basque" lang="eu" hreflang="eu" data-title="Betiereko egutegi" data-language-autonym="Euskara" data-language-local-name="Basque" class="interlanguage-link-target"><span>Euskara</span></a></li><li class="interlanguage-link interwiki-fr mw-list-item"><a href="https://fr.wikipedia.org/wiki/Calendrier_perp%C3%A9tuel" title="Calendrier perpétuel – French" lang="fr" hreflang="fr" data-title="Calendrier perpétuel" data-language-autonym="Français" data-language-local-name="French" class="interlanguage-link-target"><span>Français</span></a></li><li class="interlanguage-link interwiki-fy mw-list-item"><a href="https://fy.wikipedia.org/wiki/Ivichduorjende_kalinder" title="Ivichduorjende kalinder – Western Frisian" lang="fy" hreflang="fy" data-title="Ivichduorjende kalinder" data-language-autonym="Frysk" data-language-local-name="Western Frisian" class="interlanguage-link-target"><span>Frysk</span></a></li><li class="interlanguage-link interwiki-it mw-list-item"><a href="https://it.wikipedia.org/wiki/Calendario_perpetuo" title="Calendario perpetuo – Italian" lang="it" hreflang="it" data-title="Calendario perpetuo" data-language-autonym="Italiano" data-language-local-name="Italian" class="interlanguage-link-target"><span>Italiano</span></a></li><li class="interlanguage-link interwiki-nl mw-list-item"><a href="https://nl.wikipedia.org/wiki/Eeuwigdurende_kalender" title="Eeuwigdurende kalender – Dutch" lang="nl" hreflang="nl" data-title="Eeuwigdurende kalender" data-language-autonym="Nederlands" data-language-local-name="Dutch" class="interlanguage-link-target"><span>Nederlands</span></a></li><li class="interlanguage-link interwiki-pl mw-list-item"><a href="https://pl.wikipedia.org/wiki/Kalendarz_wieczny" title="Kalendarz wieczny – Polish" lang="pl" hreflang="pl" data-title="Kalendarz wieczny" 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/Calend%C3%A1rio_perp%C3%A9tuo" title="Calendário perpétuo – Portuguese" lang="pt" hreflang="pt" data-title="Calendário perpétuo" data-language-autonym="Português" data-language-local-name="Portuguese" class="interlanguage-link-target"><span>Português</span></a></li><li class="interlanguage-link interwiki-ru mw-list-item"><a href="https://ru.wikipedia.org/wiki/%D0%92%D0%B5%D1%87%D0%BD%D1%8B%D0%B9_%D0%BA%D0%B0%D0%BB%D0%B5%D0%BD%D0%B4%D0%B0%D1%80%D1%8C" title="Вечный календарь – Russian" lang="ru" hreflang="ru" data-title="Вечный календарь" data-language-autonym="Русский" data-language-local-name="Russian" class="interlanguage-link-target"><span>Русский</span></a></li><li class="interlanguage-link interwiki-sr badge-Q70893996 mw-list-item" title=""><a href="https://sr.wikipedia.org/wiki/Ve%C4%8Dni_kalendar" title="Večni kalendar – Serbian" lang="sr" hreflang="sr" data-title="Večni kalendar" 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/Ikuinen_kalenteri" title="Ikuinen kalenteri – Finnish" lang="fi" hreflang="fi" data-title="Ikuinen kalenteri" 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/Evighetskalender" title="Evighetskalender – Swedish" lang="sv" hreflang="sv" data-title="Evighetskalender" 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/Kalendaryong_walang-katapusan" title="Kalendaryong walang-katapusan – Tagalog" lang="tl" hreflang="tl" data-title="Kalendaryong walang-katapusan" data-language-autonym="Tagalog" data-language-local-name="Tagalog" class="interlanguage-link-target"><span>Tagalog</span></a></li><li class="interlanguage-link interwiki-uk mw-list-item"><a href="https://uk.wikipedia.org/wiki/%D0%92%D1%96%D1%87%D0%BD%D0%B8%D0%B9_%D0%BA%D0%B0%D0%BB%D0%B5%D0%BD%D0%B4%D0%B0%D1%80" title="Вічний календар – Ukrainian" lang="uk" hreflang="uk" data-title="Вічний календар" data-language-autonym="Українська" data-language-local-name="Ukrainian" class="interlanguage-link-target"><span>Українська</span></a></li><li class="interlanguage-link interwiki-zh-yue mw-list-item"><a href="https://zh-yue.wikipedia.org/wiki/%E8%90%AC%E5%B9%B4%E6%9B%86" title="萬年曆 – Cantonese" lang="yue" hreflang="yue" data-title="萬年曆" data-language-autonym="粵語" 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0.5em;text-align:center}.mw-parser-output .ambox .mbox-imageright{border:none;padding:2px 0.5em 2px 0;text-align:center}.mw-parser-output .ambox .mbox-empty-cell{border:none;padding:0;width:1px}.mw-parser-output .ambox .mbox-image-div{width:52px}@media(min-width:720px){.mw-parser-output .ambox{margin:0 10%}}@media print{body.ns-0 .mw-parser-output .ambox{display:none!important}}</style><table class="box-More_citations_needed plainlinks metadata ambox ambox-content ambox-Refimprove" role="presentation"><tbody><tr><td class="mbox-image"><div class="mbox-image-div"><span typeof="mw:File"><a href="/wiki/File:Question_book-new.svg" class="mw-file-description"><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/9/99/Question_book-new.svg/50px-Question_book-new.svg.png" decoding="async" width="50" height="39" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/9/99/Question_book-new.svg/75px-Question_book-new.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/9/99/Question_book-new.svg/100px-Question_book-new.svg.png 2x" data-file-width="512" data-file-height="399" /></a></span></div></td><td class="mbox-text"><div class="mbox-text-span">This article <b>needs additional citations for <a href="/wiki/Wikipedia:Verifiability" title="Wikipedia:Verifiability">verification</a></b>.<span class="hide-when-compact"> Please help <a href="/wiki/Special:EditPage/Perpetual_calendar" title="Special:EditPage/Perpetual calendar">improve this article</a> by <a href="/wiki/Help:Referencing_for_beginners" title="Help:Referencing for beginners">adding citations to reliable sources</a>. Unsourced material may be challenged and removed.<br /><small><span class="plainlinks"><i>Find sources:</i> <a rel="nofollow" class="external text" href="https://www.google.com/search?as_eq=wikipedia&q=%22Perpetual+calendar%22">"Perpetual calendar"</a> – <a rel="nofollow" class="external text" href="https://www.google.com/search?tbm=nws&q=%22Perpetual+calendar%22+-wikipedia&tbs=ar:1">news</a> <b>·</b> <a rel="nofollow" class="external text" href="https://www.google.com/search?&q=%22Perpetual+calendar%22&tbs=bkt:s&tbm=bks">newspapers</a> <b>·</b> <a rel="nofollow" class="external text" href="https://www.google.com/search?tbs=bks:1&q=%22Perpetual+calendar%22+-wikipedia">books</a> <b>·</b> <a rel="nofollow" class="external text" href="https://scholar.google.com/scholar?q=%22Perpetual+calendar%22">scholar</a> <b>·</b> <a rel="nofollow" class="external text" href="https://www.jstor.org/action/doBasicSearch?Query=%22Perpetual+calendar%22&acc=on&wc=on">JSTOR</a></span></small></span> <span class="date-container"><i>(<span class="date">January 2012</span>)</i></span><span class="hide-when-compact"><i> (<small><a href="/wiki/Help:Maintenance_template_removal" title="Help:Maintenance template removal">Learn how and when to remove this message</a></small>)</i></span></div></td></tr></tbody></table> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Pat248872Fig1.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/9/90/Pat248872Fig1.jpg/220px-Pat248872Fig1.jpg" decoding="async" width="220" height="248" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/9/90/Pat248872Fig1.jpg 1.5x" data-file-width="320" data-file-height="360" /></a><figcaption>Illustration from 1881 U.S. Patent 248872, for a perpetual calendar paperweight. The upper section is rotated to reveal one of seven lists of years (splitting leap years) for which the seven calendars below apply.</figcaption></figure> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:50yearcalendar.JPG" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/d/d8/50yearcalendar.JPG/220px-50yearcalendar.JPG" decoding="async" width="220" height="165" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/d/d8/50yearcalendar.JPG/330px-50yearcalendar.JPG 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/d/d8/50yearcalendar.JPG/440px-50yearcalendar.JPG 2x" data-file-width="3264" data-file-height="2448" /></a><figcaption>A 50-year "pocket calendar" that is adjusted by turning the dial to place the name of the month under the current year. One can then deduce the day of the week or the date.</figcaption></figure> <p>A <b>perpetual calendar</b> is a <a href="/wiki/Calendar" title="Calendar">calendar</a> valid for many years, usually designed to look up the <a href="/wiki/Day_of_the_week" class="mw-redirect" title="Day of the week">day of the week</a> for a given date in the past or future. </p><p>For the <a href="/wiki/Gregorian_calendar" title="Gregorian calendar">Gregorian</a> and <a href="/wiki/Julian_calendar" title="Julian calendar">Julian</a> calendars, a perpetual calendar typically consists of one of three general variations: </p> <ol><li>Fourteen one-year calendars, plus a table to show which one-year calendar is to be used for any given year. These one-year calendars divide evenly into two sets of seven calendars: seven for each common year (the year that does not have a February 29) with each of the seven starting on a different day of the week, and seven for each leap year, again with each one starting on a different day of the week, totaling fourteen. (See <a href="/wiki/Dominical_letter" title="Dominical letter">Dominical letter</a> for one common naming scheme for the 14 calendars.)</li> <li>Seven (31-day) one-month calendars (or seven each of 28–31 day month lengths, for a total of 28) and one or more tables to show which calendar is used for any given month. Some perpetual calendars' tables slide against each other so that aligning two scales with one another reveals the specific month calendar via a pointer or window mechanism.<sup id="cite_ref-1" class="reference"><a href="#cite_note-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> The seven calendars may be combined into one, either with 13 columns of which only seven are revealed,<sup id="cite_ref-2" class="reference"><a href="#cite_note-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-3" class="reference"><a href="#cite_note-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup> or with movable day-of-week names (as shown in the pocket perpetual calendar picture).</li> <li>A mixture of the above two variations - a one-year calendar in which the names of the months are fixed and the days of the week and dates are shown on movable pieces which can be swapped around as necessary.<sup id="cite_ref-4" class="reference"><a href="#cite_note-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup></li></ol> <p>Such a perpetual calendar fails to indicate the dates of <a href="/wiki/Moveable_feast" title="Moveable feast">moveable feasts</a> such as <a href="/wiki/Easter" title="Easter">Easter</a>, which are calculated based on a combination of events in the <a href="/wiki/Tropical_year" title="Tropical year">Tropical year</a> and lunar cycles. These issues are dealt with in great detail in <i><a href="/wiki/Date_of_Easter" title="Date of Easter">computus</a></i>. </p><p>An early example of a perpetual calendar for practical use is found in the <i><a href="/wiki/N%C3%BCrnberger_Handschrift_GNM_3227a" title="Nürnberger Handschrift GNM 3227a">Nürnberger Handschrift GNM 3227a</a></i>. The calendar covers the period of 1390–1495 (on which grounds the manuscript is dated to c. 1389). For each year of this period, it lists the number of weeks between <a href="/wiki/Christmas" title="Christmas">Christmas</a> and <a href="/wiki/Quinquagesima" title="Quinquagesima">Quinquagesima</a>. This is the first known instance of a tabular form of perpetual calendar allowing the calculation of the moveable feasts that became popular during the 15th century.<sup id="cite_ref-5" class="reference"><a href="#cite_note-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> </p><p>The chapel <a href="/wiki/Cappella_dei_Mercanti,_Turin" title="Cappella dei Mercanti, Turin">Cappella dei Mercanti, Turin</a> contains a perpetual calendar machine made by <a href="/wiki/Giovanni_Plana" title="Giovanni Plana">Giovanni Plana</a> using rotating drums. </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="Other_uses_of_the_term_"perpetual_calendar""><span id="Other_uses_of_the_term_.22perpetual_calendar.22"></span>Other uses of the term "perpetual calendar"</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Perpetual_calendar&action=edit&section=1" title="Edit section: Other uses of the term "perpetual calendar""><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:Breguet_MG_2575.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/b/b9/Breguet_MG_2575.jpg/220px-Breguet_MG_2575.jpg" decoding="async" width="220" height="221" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/b/b9/Breguet_MG_2575.jpg/330px-Breguet_MG_2575.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/b/b9/Breguet_MG_2575.jpg/440px-Breguet_MG_2575.jpg 2x" data-file-width="2508" data-file-height="2515" /></a><figcaption><a href="/wiki/Breguet_(brand)" title="Breguet (brand)">Breguet</a> classique <a href="/wiki/Grand_complication" class="mw-redirect" title="Grand complication">Grand complication</a> perpetual calendar</figcaption></figure> <p>Offices and retail establishments often display devices containing a set of elements to form all possible numbers from 1 through 31, as well as the names/abbreviations for the months and the days of the week, to show the current date for convenience of people who might be signing and dating documents such as <a href="/wiki/Cheque" title="Cheque">checks</a>. Establishments that serve alcoholic beverages may use a variant that shows the current month and day but subtracting the legal age of alcohol consumption in years, indicating the latest legal birth date for alcohol purchases. A common device consists of <a href="/wiki/Two-cube_calendar" title="Two-cube calendar">two cubes</a> in a holder. One cube carries the digits zero to five. The other bears the digits 0, 1, 2, 6 (or 9 if inverted), 7, and 8. This is sufficient because only one and two may appear twice in date and they are on both cubes, while the 0 is on both cubes so that all single-digit dates can be shown in double-digit format. In addition to the two cubes, three blocks, each as wide as the two cubes combined, and a third as tall and as deep, have the names of the months printed on their long faces. The current month is turned forward on the front block, with the other two month blocks behind it. </p><p>Certain <a href="/wiki/Calendar_reform" title="Calendar reform">calendar reforms</a> have been labeled perpetual calendars because their dates are fixed on the same weekdays every year. Examples are The <a href="/wiki/World_Calendar" title="World Calendar">World Calendar</a>, the <a href="/wiki/International_Fixed_Calendar" title="International Fixed Calendar">International Fixed Calendar</a> and the <a href="/wiki/Pax_Calendar" title="Pax Calendar">Pax Calendar</a>. Technically, these are not perpetual calendars but <a href="/wiki/Perennial_calendar" title="Perennial calendar">perennial calendars</a>. Their purpose, in part, is to eliminate the need for perpetual calendar tables, algorithms, and computation devices. </p> <figure class="mw-default-size mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:Patek-Philippe_MG_2583.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/2/25/Patek-Philippe_MG_2583.jpg/220px-Patek-Philippe_MG_2583.jpg" decoding="async" width="220" height="220" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/2/25/Patek-Philippe_MG_2583.jpg/330px-Patek-Philippe_MG_2583.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/2/25/Patek-Philippe_MG_2583.jpg/440px-Patek-Philippe_MG_2583.jpg 2x" data-file-width="2909" data-file-height="2912" /></a><figcaption>Perpetual calendar <a href="/wiki/Wristwatch" class="mw-redirect" title="Wristwatch">wristwatch</a> by <a href="/wiki/Patek_Philippe" title="Patek Philippe">Patek Philippe</a></figcaption></figure> <p>In <a href="/wiki/Watchmaking" class="mw-redirect" title="Watchmaking">watchmaking</a>, "perpetual calendar" describes a calendar mechanism that correctly displays the date on the <a href="/wiki/Watch" title="Watch">watch</a> "perpetually", taking into account the different lengths of the months as well as leap years. The internal mechanism will move the dial to the next day.<sup id="cite_ref-6" class="reference"><a href="#cite_note-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Algorithms">Algorithms</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Perpetual_calendar&action=edit&section=2" title="Edit section: Algorithms"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Perpetual calendars use algorithms to compute the day of the week for any given year, month, and day of the month. Even though the individual operations in the formulas can be very efficiently implemented in software, they are too complicated for most people to perform all of the arithmetic mentally.<sup id="cite_ref-7" class="reference"><a href="#cite_note-7"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup> Perpetual calendar designers hide the complexity in tables to simplify their use. </p><p>A perpetual calendar employs a <a href="/wiki/Dominical_letter#Table_of_dominical_letters_for_years" title="Dominical letter">table</a> for finding which of fourteen yearly calendars to use. A table for the Gregorian calendar expresses its 400-year grand cycle: 303 common years and 97 leap years total to 146,097 days, or exactly 20,871 weeks. This cycle breaks down into one 100-year period with 25 leap years, making 36,525 days, or <i>one</i> day less than 5,218 full weeks; and three 100-year periods with 24 leap years each, making 36,524 days, or <i>two</i> days less than 5,218 full weeks. </p><p>Within each 100-year block, the cyclic nature of the Gregorian calendar proceeds in the same fashion as its Julian predecessor: A common year begins and ends on the same day of the week, so the following year will begin on the next successive day of the week. A leap year has one more day, so the year following a leap year begins on the <i>second</i> day of the week after the leap year began. Every four years, the starting weekday advances five days, so over a 28-year period, it advances 35, returning to the same place in both the leap year progression and the starting weekday. This cycle completes three times in 84 years, leaving 16 years in the fourth, incomplete cycle of the century. </p><p>A major complicating factor in constructing a perpetual calendar algorithm is the peculiar and variable length of February, which was at one time the <i>last</i> month of the year, leaving the first 11 months March through January with a five-month repeating pattern: 31, 30, 31, 30, 31, ..., so that the offset from March of the starting day of the week for any month could be easily determined. <a href="/wiki/Zeller%27s_congruence" title="Zeller's congruence">Zeller's congruence</a>, a well-known algorithm for finding the day of the week for any date, explicitly defines January and February as the "13th" and "14th" months of the <i>previous</i> year to take advantage of this regularity, but the month-dependent calculation is still very complicated for mental arithmetic: </p> <dl><dd><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle \left\lfloor {\frac {(m+1)13}{5}}\right\rfloor \mod 7,}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mrow> <mo>⌊</mo> <mrow class="MJX-TeXAtom-ORD"> <mfrac> <mrow> <mo stretchy="false">(</mo> <mi>m</mi> <mo>+</mo> <mn>1</mn> <mo stretchy="false">)</mo> <mn>13</mn> </mrow> <mn>5</mn> </mfrac> </mrow> <mo>⌋</mo> </mrow> <mspace width="1em" /> <mi>mod</mi> <mspace width="thinmathspace" /> <mspace width="thinmathspace" /> <mn>7</mn> <mo>,</mo> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle \left\lfloor {\frac {(m+1)13}{5}}\right\rfloor \mod 7,}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/d88c353fb7cd02e75007b1282d38ee0db22e92b7" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -2.505ex; width:23.795ex; height:6.343ex;" alt="{\displaystyle \left\lfloor {\frac {(m+1)13}{5}}\right\rfloor \mod 7,}"></span></dd></dl> <p>Instead, a table-based perpetual calendar provides a simple lookup mechanism to find offset for the day of the week for the first day of each month. To simplify the table, in a leap year January and February must either be treated as a separate year or have extra entries in the month table: </p> <table class="wikitable" style="text-align:center"> <tbody><tr> <th>Month </th> <td>Jan</td> <td>Feb</td> <td>Mar</td> <td>Apr</td> <td>May</td> <td>Jun</td> <td>Jul</td> <td>Aug</td> <td>Sep</td> <td>Oct</td> <td>Nov</td> <td>Dec </td></tr> <tr> <th>Add </th> <td>0</td> <td>3</td> <td rowspan="2">3</td> <td rowspan="2">6</td> <td rowspan="2">1</td> <td rowspan="2">4</td> <td rowspan="2">6</td> <td rowspan="2">2</td> <td rowspan="2">5</td> <td rowspan="2">0</td> <td rowspan="2">3</td> <td rowspan="2">5 </td></tr> <tr> <th>For leap years </th> <td>6</td> <td>2 </td></tr></tbody></table> <div class="mw-heading mw-heading2"><h2 id="Perpetual_Julian_and_Gregorian_calendar_tables">Perpetual Julian and Gregorian calendar tables</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Perpetual_calendar&action=edit&section=3" title="Edit section: Perpetual Julian and Gregorian calendar tables"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <div class="mw-heading mw-heading3"><h3 id="Table_one_(cyd)"><span id="Table_one_.28cyd.29"></span>Table one (cyd)</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Perpetual_calendar&action=edit&section=4" title="Edit section: Table one (cyd)"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The following calendar works for any date from 15 October 1582 onwards, but only for Gregorian calendar dates. </p> <figure class="mw-default-size mw-halign-center" typeof="mw:File/Thumb"><a href="/wiki/File:Permanent_Calendar_gregorian.png" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/7/74/Permanent_Calendar_gregorian.png/880px-Permanent_Calendar_gregorian.png" decoding="async" width="880" height="558" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/7/74/Permanent_Calendar_gregorian.png/1320px-Permanent_Calendar_gregorian.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/7/74/Permanent_Calendar_gregorian.png/1760px-Permanent_Calendar_gregorian.png 2x" data-file-width="2241" data-file-height="1422" /></a><figcaption>A genuinely perpetual calendar, which allows its user to look up the day of the week for any Gregorian date.</figcaption></figure> <div style="clear:both;" class=""></div> <div class="mw-heading mw-heading3"><h3 id="Table_two_(cymd)"><span id="Table_two_.28cymd.29"></span>Table two (cymd)</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Perpetual_calendar&action=edit&section=5" title="Edit section: Table two (cymd)"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <table class="wikitable"> <tbody><tr> <td colspan="7" rowspan="19" style="vertical-align:top; background-color:Honeydew"> </td> <th colspan="7"><div class="center" style="width:auto; margin-left:auto; margin-right:auto;">Years of the century</div> </th> <td colspan="6" rowspan="19" style="vertical-align:top; background-color:Honeydew"><div class="center" style="width:auto; margin-left:auto; margin-right:auto;"><i>Example 1</i></div> <p><i>Gregorian 31 March 2006:</i> Greg century 20(c) and year 06(y) meet at A in the table of <i>Latin square</i>. The A in row Mar(m) meets 31(d) at Fri in the table of <i>Weekdays</i>. The day is Friday. </p> <div class="center" style="width:auto; margin-left:auto; margin-right:auto;"><i>Example 2</i></div> <p><i>BC 1 January 45:</i> BC 45 = -44 = -100 + 56 (a leap year). -1 and 56 meet at B and <span style="color:#ff0000;">Jan</span>_B meets 1 at Fri(day). </p> <div class="center" style="width:auto; margin-left:auto; margin-right:auto;"><i>Example 3</i></div> <p><i>Julian 1 January 1900:</i> Julian 19 meets 00 at A and <span style="color:#ff0000;">Jan</span>_A meets 1 at Sat(urday). </p> <div class="center" style="width:auto; margin-left:auto; margin-right:auto;"><i>Example 4</i></div> <p><i>Gregorian 1 January 1900:</i> Greg 19 meets 00 at G and Jan_G meets 1 at Mon(day). </p> </td></tr> <tr> <td><b>00</b></td> <td>01</td> <td>02</td> <td>03</td> <td> </td> <td><span style="color:#ff0000;"><b>04</b></span></td> <td>05 </td></tr> <tr> <td>06</td> <td>07</td> <td> </td> <td><span style="color:#ff0000;"><b>08</b></span></td> <td>09</td> <td>10</td> <td>11 </td></tr> <tr> <td> </td> <td><span style="color:#ff0000;"><b>12</b></span></td> <td>13</td> <td>14</td> <td>15</td> <td> </td> <td><span style="color:#ff0000;"><b>16</b></span> </td></tr> <tr> <td>17</td> <td>18</td> <td>19</td> <td> </td> <td><span style="color:#ff0000;"><b>20</b></span></td> <td>21</td> <td>22 </td></tr> <tr> <td>23</td> <td> </td> <td><span style="color:#ff0000;"><b>24</b></span></td> <td>25</td> <td>26</td> <td>27</td> <td>  </td></tr> <tr> <td><span style="color:#ff0000;"><b>28</b></span></td> <td>29</td> <td>30</td> <td>31</td> <td> </td> <td><span style="color:#ff0000;"><b>32</b></span></td> <td>33 </td></tr> <tr> <td>34</td> <td>35</td> <td> </td> <td><span style="color:#ff0000;"><b>36</b></span></td> <td>37</td> <td>38</td> <td>39 </td></tr> <tr> <td> </td> <td><span style="color:#ff0000;"><b>40</b></span></td> <td>41</td> <td>42</td> <td>43</td> <td> </td> <td><span style="color:#ff0000;"><b>44</b></span> </td></tr> <tr> <td>45</td> <td>46</td> <td>47</td> <td> </td> <td><span style="color:#ff0000;"><b>48</b></span></td> <td>49</td> <td>50 </td></tr> <tr> <td>51</td> <td> </td> <td><span style="color:#ff0000;"><b>52</b></span></td> <td>53</td> <td>54</td> <td>55</td> <td>  </td></tr> <tr> <td><span style="color:#ff0000;"><b>56</b></span></td> <td>57</td> <td>58</td> <td>59</td> <td> </td> <td><span style="color:#ff0000;"><b>60</b></span></td> <td>61 </td></tr> <tr> <td>62</td> <td>63</td> <td> </td> <td><span style="color:#ff0000;"><b>64</b></span></td> <td>65</td> <td>66</td> <td>67 </td></tr> <tr> <td> </td> <td><span style="color:#ff0000;"><b>68</b></span></td> <td>69</td> <td>70</td> <td>71</td> <td> </td> <td><span style="color:#ff0000;"><b>72</b></span> </td></tr> <tr> <td>73</td> <td>74</td> <td>75</td> <td> </td> <td><span style="color:#ff0000;"><b>76</b></span></td> <td>77</td> <td>78 </td></tr> <tr> <td>79</td> <td> </td> <td><span style="color:#ff0000;"><b>80</b></span></td> <td>81</td> <td>82</td> <td>83</td> <td>  </td></tr> <tr> <td><span style="color:#ff0000;"><b>84</b></span></td> <td>85</td> <td>86</td> <td>87</td> <td> </td> <td><span style="color:#ff0000;"><b>88</b></span></td> <td>89 </td></tr> <tr> <td>90</td> <td>91</td> <td> </td> <td><span style="color:#ff0000;"><b>92</b></span></td> <td>93</td> <td>94</td> <td>95 </td></tr> <tr> <td> </td> <td><span style="color:#ff0000;"><b>96</b></span></td> <td>97</td> <td>98</td> <td>99</td> <td> </td> <td>  </td></tr> <tr style="text-align:center"> <td colspan="6"><b>Centuries</b> </td> <td rowspan="9">  </td> <td colspan="7" rowspan="2"><b>Latin square</b> </td> <td rowspan="9">  </td> <td colspan="6" rowspan="2"><b>Months</b> </td></tr> <tr style="text-align:center"> <td colspan="4">Julian</td> <td colspan="2">Greg. </td></tr> <tr style="text-align:center"> <td style="text-align:right"><span style=";""><b>-4</b></span> </td> <td style="text-align:right"><span style=";""><b> 3</b></span> </td> <td style="text-align:right"><span style=";""><b>10</b></span> </td> <td style="text-align:right"><span style=";""><b>17</b></span> </td> <td style="text-align:right">— </td> <td style="text-align:right">— </td> <td>F</td> <td>E</td> <td>D</td> <td>C</td> <td>B</td> <td>A</td> <td>G</td> <td><span style="color:#ff0000;"><b>Jan</b></span></td> <td> </td> <td>Apr</td> <td>Jul</td> <td>  </td></tr> <tr style="text-align:center"> <td style="text-align:right"><span style=";""><b>-3</b></span> </td> <td style="text-align:right"><span style=";""><b>4</b></span> </td> <td style="text-align:right"><span style=";""><b>11</b></span> </td> <td style="text-align:right"><span style=";""><b>18</b></span> </td> <td style="text-align:right">15 </td> <td style="text-align:right">19 </td> <td>G</td> <td>F</td> <td>E</td> <td>D</td> <td>C</td> <td>B</td> <td>A</td> <td>Jan</td> <td> </td> <td> </td> <td> </td> <td>Oct </td></tr> <tr style="text-align:center"> <td style="text-align:right"><span style=";""><b>-2</b></span> </td> <td style="text-align:right"><span style=";""><b>5</b></span> </td> <td style="text-align:right"><span style=";""><b>12</b></span> </td> <td style="text-align:right"><span style=";""><b>19</b></span> </td> <td style="text-align:right"><span style=";""><b>16</b></span> </td> <td style="text-align:right"><span style=";""><b>20</b></span> </td> <td>A</td> <td>G</td> <td>F</td> <td>E</td> <td>D</td> <td>C</td> <td>B</td> <td> </td> <td> </td> <td>May</td> <td> </td> <td>  </td></tr> <tr style="text-align:center"> <td style="text-align:right"><span style=";""><b>-1</b></span> </td> <td style="text-align:right"><span style=";""><b>6</b></span> </td> <td style="text-align:right"><span style=";""><b>13</b></span> </td> <td style="text-align:right"><span style=";""><b>20</b></span> </td> <td style="text-align:right">— </td> <td style="text-align:right">— </td> <td>B</td> <td>A</td> <td>G</td> <td>F</td> <td>E</td> <td>D</td> <td>C</td> <td><span style="color:#ff0000;"><b>Feb</b></span></td> <td> </td> <td> </td> <td>Aug</td> <td>  </td></tr> <tr style="text-align:center"> <td style="text-align:right"><span style=";""><b>0</b></span> </td> <td style="text-align:right"><span style=";""><b>7</b></span> </td> <td style="text-align:right"><span style=";""><b>14</b></span> </td> <td style="text-align:right"><span style=";""><b>21</b></span> </td> <td style="text-align:right">17 </td> <td style="text-align:right">21 </td> <td>C</td> <td>B</td> <td>A</td> <td>G</td> <td>F</td> <td>E</td> <td>D</td> <td>Feb</td> <td>Mar</td> <td> </td> <td> </td> <td>Nov </td></tr> <tr style="text-align:center"> <td style="text-align:right"><span style=";""><b>1</b></span> </td> <td style="text-align:right"><span style=";""><b>8</b></span> </td> <td style="text-align:right"><span style=";""><b>15</b></span> </td> <td style="text-align:right"><span style=";""><b>22</b></span> </td> <td style="text-align:right">— </td> <td style="text-align:right">— </td> <td>D</td> <td>C</td> <td>B</td> <td>A</td> <td>G</td> <td>F</td> <td>E</td> <td> </td> <td> </td> <td>Jun</td> <td> </td> <td>  </td></tr> <tr style="text-align:center"> <td style="text-align:right"><span style=";""><b>2</b></span> </td> <td style="text-align:right"><span style=";""><b>9</b></span> </td> <td style="text-align:right"><span style=";""><b>16</b></span> </td> <td style="text-align:right"><span style=";""><b>23</b></span> </td> <td style="text-align:right">18 </td> <td style="text-align:right">22 </td> <td>E</td> <td>D</td> <td>C</td> <td>B</td> <td>A</td> <td>G</td> <td>F</td> <td> </td> <td> </td> <td> </td> <td>Sep</td> <td>Dec </td></tr> <tr style="text-align:center"> <td rowspan="8">  </td> <td colspan="5"><b>Days</b> </td> <td rowspan="8">  </td> <td colspan="7"><b>Weekdays</b> </td> <td colspan="1" rowspan="8">  </td> <td colspan="5" rowspan="8" style="text-align:left; background-color:Honeydew"> </td></tr> <tr style="text-align:center"> <td>1</td> <td>8</td> <td>15</td> <td>22</td> <td>29</td> <td>Mon</td> <td>Tue</td> <td>Wed</td> <td>Thu</td> <td>Fri</td> <td>Sat</td> <td>Sun </td></tr> <tr style="text-align:center"> <td>2</td> <td>9</td> <td>16</td> <td>23</td> <td>30</td> <td>Tue</td> <td>Wed</td> <td>Thu</td> <td>Fri</td> <td>Sat</td> <td>Sun</td> <td>Mon </td></tr> <tr style="text-align:center"> <td>3</td> <td>10</td> <td>17</td> <td>24</td> <td>31</td> <td>Wed</td> <td>Thu</td> <td>Fri</td> <td>Sat</td> <td>Sun</td> <td>Mon</td> <td>Tue </td></tr> <tr style="text-align:center"> <td>4</td> <td>11</td> <td>18</td> <td>25</td> <td> </td> <td>Thu</td> <td>Fri</td> <td>Sat</td> <td>Sun</td> <td>Mon</td> <td>Tue</td> <td>Wed </td></tr> <tr style="text-align:center"> <td>5</td> <td>12</td> <td>19</td> <td>26</td> <td> </td> <td>Fri</td> <td>Sat</td> <td>Sun</td> <td>Mon</td> <td>Tue</td> <td>Wed</td> <td>Thu </td></tr> <tr style="text-align:center"> <td>6</td> <td>13</td> <td>20</td> <td>27</td> <td> </td> <td>Sat</td> <td>Sun</td> <td>Mon</td> <td>Tue</td> <td>Wed</td> <td>Thu</td> <td>Fri </td></tr> <tr style="text-align:center"> <td>7</td> <td>14</td> <td>21</td> <td>28</td> <td> </td> <td>Sun</td> <td>Mon</td> <td>Tue</td> <td>Wed</td> <td>Thu</td> <td>Fri</td> <td>Sat </td></tr></tbody></table> <table class="wikitable" style="text-align:center"> <tbody><tr> <td><b>Julian</b><br /><b>centuries</b></td> <td><b>Gregorian</b><br /><b>centuries</b></td> <td rowspan="8"></td> <td colspan="7"><b>Days of the week</b></td> <td rowspan="8"></td> <td colspan="5"><b>Months</b></td> <td rowspan="8"></td> <td colspan="5"><b>Days</b> </td></tr> <tr> <td><span style="color:red;">04 11 18 </span></td> <td>19 23 27</td> <td>Sun</td> <td>Mon</td> <td>Tue</td> <td>Wed</td> <td>Thu</td> <td>Fri</td> <td>Sat</td> <td><span style="color:red;">Jan</span></td> <td>Apri</td> <td>Jul</td> <td></td> <td></td> <td>01</td> <td>08</td> <td>15</td> <td>22</td> <td>29 </td></tr> <tr> <td><span style="color:red;">03 10 17</span></td> <td></td> <td>Mon</td> <td>Tue</td> <td>Wed</td> <td>Thu</td> <td>Fri</td> <td>Sat</td> <td>Sun</td> <td></td> <td></td> <td></td> <td>Sep</td> <td>Dec</td> <td>02</td> <td>09</td> <td>16</td> <td>23</td> <td>30 </td></tr> <tr> <td><span style="color:red;">02 09 16</span></td> <td>18 22 26</td> <td>Tue</td> <td>Wed</td> <td>Thu</td> <td>Fri</td> <td>Sat</td> <td>Sun</td> <td>Mon</td> <td></td> <td></td> <td>Jun</td> <td></td> <td></td> <td>03</td> <td>10</td> <td>17</td> <td>24</td> <td>31 </td></tr> <tr> <td><span style="color:red;">01 08 15</span></td> <td></td> <td>Wed</td> <td>Thu</td> <td>Fri</td> <td>Sat</td> <td>Sun</td> <td>Mon</td> <td>Tue</td> <td>Feb</td> <td>Mar</td> <td></td> <td></td> <td>Nov</td> <td>04</td> <td>11</td> <td>18</td> <td>25</td> <td> </td></tr> <tr> <td><span style="color:red;">00 07 14</span></td> <td>17 21 25</td> <td>Thu</td> <td>Fri</td> <td>Sat</td> <td>Sun</td> <td>Mon</td> <td>Tue</td> <td>Wed</td> <td><span style="color:red;">Feb</span></td> <td></td> <td></td> <td>Aug</td> <td></td> <td>05</td> <td>12</td> <td>19</td> <td>26</td> <td> </td></tr> <tr> <td><span style="color:red;">–1 06 13</span></td> <td></td> <td>Fri</td> <td>Sat</td> <td>Sun</td> <td>Mon</td> <td>Tue</td> <td>Wed</td> <td>Thu</td> <td></td> <td></td> <td>May</td> <td></td> <td></td> <td>06</td> <td>13</td> <td>20</td> <td>27</td> <td> </td></tr> <tr> <td><span style="color:red;">–2 05 12</span></td> <td><span style="color:red;">16 20 24</span></td> <td>Sat</td> <td>Sun</td> <td>Mon</td> <td>Tue</td> <td>Wed</td> <td>Thu</td> <td>Fri</td> <td>Jan</td> <td></td> <td></td> <td></td> <td>Oct</td> <td>07</td> <td>14</td> <td>21</td> <td>28</td> <td> </td></tr> <tr> <td colspan="22"> </td></tr> <tr> <td colspan="3" rowspan="18"><b>Years</b></td> <td><span style="color:red;">0</span>0 </td> <td>01 </td> <td>02</td> <td>03</td> <td></td> <td><span style="color:red;">04</span></td> <td>05 </td></tr> <tr> <td>06</td> <td>07</td> <td></td> <td><span style="color:red;">08</span></td> <td>09</td> <td>10</td> <td>11 </td></tr> <tr> <td></td> <td><span style="color:red;">12</span></td> <td>13</td> <td>14</td> <td>15</td> <td></td> <td><span style="color:red;">16</span> </td></tr> <tr> <td>17</td> <td>18</td> <td>19</td> <td></td> <td><span style="color:red;">20</span></td> <td>21</td> <td>22 </td></tr> <tr> <td>23</td> <td></td> <td><span style="color:red;">24</span></td> <td>25</td> <td>26</td> <td>27</td> <td> </td></tr> <tr> <td><span style="color:red;">28</span></td> <td>29</td> <td>30</td> <td>31</td> <td></td> <td><span style="color:red;">32</span></td> <td>33 </td></tr> <tr> <td>34</td> <td>35</td> <td></td> <td><span style="color:red;">36</span></td> <td>37</td> <td>38</td> <td>39 </td></tr> <tr> <td></td> <td><span style="color:red;">40</span></td> <td>41</td> <td>42</td> <td>43</td> <td></td> <td><span style="color:red;">44</span> </td></tr> <tr> <td>45</td> <td>46</td> <td>47</td> <td></td> <td><span style="color:red;">48</span></td> <td>49</td> <td>50 </td></tr> <tr> <td>51</td> <td></td> <td><span style="color:red;">52</span></td> <td>53</td> <td>54</td> <td>55</td> <td> </td></tr> <tr> <td><span style="color:red;">56</span></td> <td>57</td> <td>58</td> <td>59</td> <td></td> <td><span style="color:red;">60</span></td> <td>61 </td></tr> <tr> <td>62</td> <td>63</td> <td></td> <td><span style="color:red;">64</span></td> <td>65</td> <td>66</td> <td>67 </td></tr> <tr> <td></td> <td><span style="color:red;">68</span></td> <td>69</td> <td>70</td> <td>71</td> <td></td> <td><span style="color:red;">72</span> </td></tr> <tr> <td>73</td> <td>74</td> <td>75</td> <td></td> <td><span style="color:red;">76</span></td> <td>77</td> <td>78 </td></tr> <tr> <td>79</td> <td></td> <td><span style="color:red;">80</span></td> <td>81</td> <td>82</td> <td>83</td> <td> </td></tr> <tr> <td><span style="color:red;">84</span></td> <td>85</td> <td>86</td> <td>87</td> <td></td> <td><span style="color:red;">88</span></td> <td>89 </td></tr> <tr> <td>90</td> <td>91</td> <td></td> <td><span style="color:red;">92</span></td> <td>93</td> <td>94</td> <td>95 </td></tr> <tr> <td></td> <td><span style="color:red;">96</span></td> <td>97</td> <td>98</td> <td>99</td> <td></td> <td> </td></tr></tbody></table> <div class="mw-heading mw-heading3"><h3 id="Table_three_(dmyc)"><span id="Table_three_.28dmyc.29"></span>Table three (dmyc)</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Perpetual_calendar&action=edit&section=6" title="Edit section: Table three (dmyc)"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <table class="wikitable" style="text-align:center"> <tbody><tr> <th>#</th> <th>Julian<br />centuries<br />(mod 7)</th> <th>Gregorian<br />centuries<br />(mod 4)</th> <th colspan="3">Dates </th> <td>01<br />08<br />15<br />22<br />29</td> <td>02<br />09<br />16<br />23<br />30</td> <td>03<br />10<br />17<br />24<br />31</td> <td>04<br />11<br />18<br />25<br /> <br /></td> <td>05<br />12<br />19<br />26<br /> <br /></td> <td>06<br />13<br />20<br />27<br /> <br /></td> <td>07<br />14<br />21<br />28<br /> <br /> </td> <th colspan="18">Years of the century (mod 28) </th></tr> <tr> <th>6 </th> <td style="background-color: lightgreen"><span style="color:red;">05 12 19</span></td> <td style="background-color: lightgreen"><span style="color:red;">16 20 24</span></td> <td>Apr</td> <td>Jul</td> <td><span style="color:red;">Jan</span></td> <td style="background-color: lightgreen"><span style="color:blue;">Sun</span></td> <td style="background-color: lightgreen">Mon</td> <td style="background-color: lightgreen">Tue</td> <td style="background-color: lightgreen">Wed</td> <td style="background-color: lightgreen">Thu</td> <td style="background-color: lightgreen">Fri</td> <td style="background-color: lightgreen">Sat</td> <td>01</td> <td>07</td> <td><span style="color:red;">12</span></td> <td>18</td> <td></td> <td>29</td> <td>35</td> <td><span style="color:red;">40</span></td> <td>46</td> <td></td> <td>57</td> <td>63</td> <td><span style="color:red;">68</span></td> <td>74</td> <td></td> <td>85</td> <td>91</td> <td><span style="color:red;">96</span> </td></tr> <tr> <th>5 </th> <td><span style="color:red;">06 13 20</span></td> <td></td> <td>Sep</td> <td>Dec</td> <td></td> <td><span style="color:blue;">Sat</span></td> <td>Sun</td> <td>Mon</td> <td>Tue</td> <td>Wed</td> <td>Thu</td> <td>Fri</td> <td>02</td> <td></td> <td>13</td> <td>19</td> <td><span style="color:red;">24</span></td> <td>30</td> <td></td> <td>41</td> <td>47</td> <td><span style="color:red;">52</span></td> <td>58</td> <td></td> <td>69</td> <td>75</td> <td><span style="color:red;">80</span></td> <td>86</td> <td></td> <td>97 </td></tr> <tr> <th>4 </th> <td style="background-color: yellow"><span style="color:red;">07 14 21</span></td> <td style="background-color: yellow">17 21 25</td> <td>Jun</td> <td></td> <td></td> <td style="background-color: yellow"><span style="color:blue;">Fri</span></td> <td style="background-color: yellow">Sat</td> <td style="background-color: yellow">Sun</td> <td style="background-color: yellow">Mon</td> <td style="background-color: yellow">Tue</td> <td style="background-color: yellow">Wed</td> <td style="background-color: yellow">Thu</td> <td>03</td> <td><span style="color:red;">08</span></td> <td>14</td> <td></td> <td>25</td> <td>31</td> <td><span style="color:red;">36</span></td> <td>42</td> <td></td> <td>53</td> <td>59</td> <td><span style="color:red;">64</span></td> <td>70</td> <td></td> <td>81</td> <td>87</td> <td><span style="color:red;">92</span></td> <td>98 </td></tr> <tr> <th>3 </th> <td><span style="color:red;">08 15 22</span></td> <td></td> <td>Feb</td> <td>Mar</td> <td>Nov</td> <td><span style="color:blue;">Thu</span></td> <td>Fri</td> <td>Sat</td> <td>Sun</td> <td>Mon</td> <td>Tue</td> <td>Wed</td> <td></td> <td>09</td> <td>15</td> <td><span style="color:red;">20</span></td> <td>26</td> <td></td> <td>37</td> <td>43</td> <td><span style="color:red;">48</span></td> <td>54</td> <td></td> <td>65</td> <td>71</td> <td><span style="color:red;">76</span></td> <td>82</td> <td></td> <td>93</td> <td>99 </td></tr> <tr> <th>2 </th> <td style="background-color: pink"><span style="color:red;">09 16 23</span></td> <td style="background-color: pink">18 22 26</td> <td>Aug</td> <td><span style="color:red;">Feb</span></td> <td></td> <td style="background-color: pink"><span style="color:blue;">Wed</span></td> <td style="background-color: pink">Thu</td> <td style="background-color: pink">Fri</td> <td style="background-color: pink">Sat</td> <td style="background-color: pink">Sun</td> <td style="background-color: pink">Mon</td> <td style="background-color: pink">Tue</td> <td><span style="color:red;">04</span></td> <td>10</td> <td></td> <td>21</td> <td>27</td> <td><span style="color:red;">32</span></td> <td>38</td> <td></td> <td>49</td> <td>55</td> <td><span style="color:red;">60</span></td> <td>66</td> <td></td> <td>77</td> <td>83</td> <td><span style="color:red;">88</span></td> <td>94</td> <td> </td></tr> <tr> <th>1 </th> <td><span style="color:red;">10 17 24</span></td> <td></td> <td>May</td> <td></td> <td></td> <td><span style="color:blue;">Tue</span></td> <td>Wed</td> <td>Thu</td> <td>Fri</td> <td>Sat</td> <td>Sun</td> <td>Mon</td> <td>05</td> <td>11</td> <td><span style="color:red;">16</span></td> <td>22</td> <td></td> <td>33</td> <td>39</td> <td><span style="color:red;">44</span></td> <td>50</td> <td></td> <td>61</td> <td>67</td> <td><span style="color:red;">72</span></td> <td>78</td> <td></td> <td>89</td> <td>95</td> <td> </td></tr> <tr> <th>0 </th> <td style="background-color: orange"><span style="color:red;">11 18 25</span></td> <td style="background-color: orange">19 23 27</td> <td>Jan</td> <td>Oct</td> <td></td> <td style="background-color: orange"><span style="color:blue;">Mon</span></td> <td style="background-color: orange"><span style="color:blue;">Tue</span></td> <td style="background-color: orange"><span style="color:blue;">Wed</span></td> <td style="background-color: orange"><span style="color:blue;">Thu</span></td> <td style="background-color: orange"><span style="color:blue;">Fri</span></td> <td style="background-color: orange"><span style="color:blue;">Sat</span></td> <td style="background-color: orange"><span style="color:blue;">Sun</span></td> <td>06</td> <td></td> <td>17</td> <td>23</td> <td><span style="color:red;">28</span></td> <td>34</td> <td></td> <td>45</td> <td>51</td> <td><span style="color:red;">56</span></td> <td>62</td> <td></td> <td>73</td> <td>79</td> <td><span style="color:red;">84</span></td> <td>90</td> <td></td> <td><span style="color:red;">0</span>0 </td></tr></tbody></table> <p><br /> </p> <div class="mw-heading mw-heading2"><h2 id="See_also">See also</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Perpetual_calendar&action=edit&section=7" title="Edit section: See also"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a href="/wiki/Determination_of_the_day_of_the_week" title="Determination of the day of the week">Determination of the day of the week</a></li> <li><a href="/wiki/Doomsday_rule" title="Doomsday rule">Doomsday rule</a></li> <li><a href="/wiki/Long_Now_Foundation" title="Long Now Foundation">Long Now Foundation</a></li> <li><a href="/wiki/Year_10,000_problem" class="mw-redirect" title="Year 10,000 problem">Year 10,000 problem</a></li></ul> <div class="mw-heading mw-heading2"><h2 id="References">References</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Perpetual_calendar&action=edit&section=8" title="Edit section: References"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></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"> <div class="mw-references-wrap"><ol class="references"> <li id="cite_note-1"><span class="mw-cite-backlink"><b><a href="#cite_ref-1">^</a></b></span> <span class="reference-text"><span><a rel="nofollow" class="external text" href="https://patents.google.com/patent/US1042337">U.S. patent 1,042,337</a></span>, "<i>Calendar (Fred P. Gorin)</i>".</span> </li> <li id="cite_note-2"><span class="mw-cite-backlink"><b><a href="#cite_ref-2">^</a></b></span> <span class="reference-text"><span><a rel="nofollow" class="external text" href="https://patents.google.com/patent/US248872">U.S. patent 248,872</a></span>, "<i>Calendar (Robert McCurdy)</i>".</span> </li> <li id="cite_note-3"><span class="mw-cite-backlink"><b><a href="#cite_ref-3">^</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="http://www.httpro.com/aluminum-perpetual-calendars.html">"Aluminum Perpetual Calendar"</a>. 17 September 2011.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Aluminum+Perpetual+Calendar&rft.date=2011-09-17&rft_id=http%3A%2F%2Fwww.httpro.com%2Faluminum-perpetual-calendars.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3APerpetual+calendar" class="Z3988"></span></span> </li> <li id="cite_note-4"><span class="mw-cite-backlink"><b><a href="#cite_ref-4">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFDoerfler2019" class="citation web cs1">Doerfler, Ronald W (29 August 2019). <a rel="nofollow" class="external text" href="http://deadreckonings.com">"A 2010 "graphical computing" calendar"</a><span class="reference-accessdate">. Retrieved <span class="nowrap">30 August</span> 2019</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=A+2010+%22graphical+computing%22+calendar&rft.date=2019-08-29&rft.aulast=Doerfler&rft.aufirst=Ronald+W&rft_id=http%3A%2F%2Fdeadreckonings.com&rfr_id=info%3Asid%2Fen.wikipedia.org%3APerpetual+calendar" class="Z3988"></span></span> </li> <li id="cite_note-5"><span class="mw-cite-backlink"><b><a href="#cite_ref-5">^</a></b></span> <span class="reference-text">Trude Ehlert, Rainer Leng, <i>Frühe Koch- und Pulverrezepte aus der Nürnberger Handschrift GNM 3227a (um 1389)</i>; in: <i>Medizin in Geschichte, Philologie und Ethnologie</i> (2003), p. 291.</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"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://chestofbooks.com/crafts/mechanics/Cyclopaedia/Mechanism-Of-Perpetual-Calendar-Watch.html">"Mechanism Of Perpetual Calendar Watch"</a>. 17 September 2011.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Mechanism+Of+Perpetual+Calendar+Watch&rft.date=2011-09-17&rft_id=http%3A%2F%2Fchestofbooks.com%2Fcrafts%2Fmechanics%2FCyclopaedia%2FMechanism-Of-Perpetual-Calendar-Watch.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3APerpetual+calendar" 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">But see the formula in the preceding section, which is very easy to memorize.</span> </li> </ol></div></div> <div class="mw-heading mw-heading2"><h2 id="External_links">External links</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Perpetual_calendar&action=edit&section=9" title="Edit section: External links"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></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:r1237033735">@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-en-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-en-v2.svg"]{background-color:white}}</style><div class="side-box side-box-right plainlinks sistersitebox"><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="side-box-flex"> <div class="side-box-image"><span class="noviewer" typeof="mw:File"><span><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/4/4a/Commons-logo.svg/30px-Commons-logo.svg.png" decoding="async" width="30" height="40" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/4/4a/Commons-logo.svg/45px-Commons-logo.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/4/4a/Commons-logo.svg/59px-Commons-logo.svg.png 2x" data-file-width="1024" data-file-height="1376" /></span></span></div> <div class="side-box-text plainlist">Wikimedia Commons has media related to <span style="font-weight: bold; font-style: italic;"><a href="https://commons.wikimedia.org/wiki/Category:Perpetual_calendars" class="extiw" title="commons:Category:Perpetual calendars">Perpetual calendars</a></span>.</div></div> </div> <ul><li><a rel="nofollow" class="external text" href="https://drive.google.com/file/d/1KnuzlpBQhwyr107qI1XbLNQeLsES3VGC/view?usp=sharing">Sliding Perpetual Calendar on one sheet of paper (U.S. version, PDF)</a></li> <li><a rel="nofollow" class="external text" href="https://drive.google.com/file/d/1XGtb-KV3tkA0_HXqINqibB4C_gIq7s-H/view?usp=sharing">Sliding Perpetual Calendar on one sheet of paper (non U.S. version, PDF)</a></li> <li><a rel="nofollow" class="external text" href="https://drive.google.com/file/d/1aD3qR1DYkGyes7ADZnOO4vCtEDH32Ch8/view?usp=sharing">Conical or Pyramidal Year Calendar (with "First of March table", PDF)</a></li> <li><a rel="nofollow" class="external text" href="http://newperpetualcalendar.yolasite.com/">New Perpetual Calendar for any year</a></li> <li><a rel="nofollow" class="external text" href="https://alokmenghrajani.github.io/perpetual_calendar/">Perpetual Calendar in JavaScript</a></li></ul> <div class="navbox-styles"><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 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.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:Calendars" title="Template:Calendars"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:Calendars" title="Template talk:Calendars"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:Calendars" title="Special:EditPage/Template:Calendars"><abbr title="Edit this template">e</abbr></a></li></ul></div><div id="Calendars" style="font-size:114%;margin:0 4em"><a href="/wiki/Calendar" title="Calendar">Calendars</a></div></th></tr><tr><th scope="row" class="navbox-group" style="width:1%">Systems</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/Lunar_calendar" title="Lunar calendar">Lunar</a></li> <li><a href="/wiki/Lunisolar_calendar" title="Lunisolar calendar">Lunisolar</a></li> <li><a href="/wiki/Solar_calendar" title="Solar calendar">Solar</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">In wide use</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/Astronomical_year_numbering" title="Astronomical year numbering">Astronomical</a></li> <li><a href="/wiki/Buddhist_calendar" title="Buddhist calendar">Buddhist</a></li> <li><a href="/wiki/Chinese_calendar" title="Chinese calendar">Chinese</a></li> <li><a href="/wiki/Ethiopian_calendar" title="Ethiopian calendar">Ethiopian</a></li> <li><a href="/wiki/Gregorian_calendar" title="Gregorian calendar">Gregorian</a></li> <li><a href="/wiki/Hindu_calendar" title="Hindu calendar">Hindu</a></li> <li><a href="/wiki/Islamic_calendar" title="Islamic calendar">Lunar Hijri</a></li> <li><a href="/wiki/Solar_Hijri_calendar" title="Solar Hijri calendar">Solar Hijri</a></li> <li><a href="/wiki/ISO_week_date" title="ISO week date">ISO</a></li> <li><a href="/wiki/Unix_time" title="Unix time">Unix time</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><div style="display: inline-block; line-height: 1.2em; padding: .1em 0;">In more<br />limited use</div></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><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Akan_calendar" title="Akan calendar">Akan</a></li> <li><a href="/wiki/Armenian_calendar" title="Armenian calendar">Armenian</a></li> <li><a href="/wiki/Assamese_calendar" title="Assamese calendar">Assamese (Bhāshkarābda)</a></li> <li><a href="/wiki/Assyrian_calendar" title="Assyrian calendar">Assyrian</a></li> <li><a href="/wiki/Bah%C3%A1%CA%BC%C3%AD_calendar" title="Baháʼí calendar">Baháʼí</a> <ul><li>Badí‘</li></ul></li> <li>Bali <ul><li><a href="/wiki/Pawukon_calendar" title="Pawukon calendar">Pawukon</a></li> <li><a href="/wiki/Balinese_saka_calendar" title="Balinese saka calendar">Saka</a></li></ul></li> <li><a href="/wiki/Bengali_calendars" title="Bengali calendars">Bengali</a> <ul><li><a href="/wiki/Bangladeshi_calendar" class="mw-redirect" title="Bangladeshi calendar">Bangladeshi</a></li></ul></li> <li><a href="/wiki/Berber_calendar" title="Berber calendar">Berber</a></li> <li><a href="/wiki/Borana_calendar" title="Borana calendar">Borana</a></li> <li><a href="/wiki/Burmese_calendar" title="Burmese calendar">Burmese</a></li> <li><a href="/wiki/Chinese_calendar" title="Chinese calendar">Chinese</a> <ul><li><a href="/wiki/Earthly_Branches" title="Earthly Branches">Earthly Branches</a></li> <li><a href="/wiki/Heavenly_Stems" title="Heavenly Stems">Heavenly Stems</a></li> <li><a href="/wiki/Republic_of_China_calendar" title="Republic of China calendar">Minguo</a></li> <li><a href="/wiki/Solar_term" title="Solar term">Solar term</a></li></ul></li> <li><a href="/wiki/Heathen_holidays" title="Heathen holidays">Germanic heathen</a></li> <li><a href="/wiki/Georgian_calendar" title="Georgian calendar">Georgian</a></li> <li><a href="/wiki/Hebrew_calendar" title="Hebrew calendar">Hebrew</a></li> <li><a href="/wiki/Hindu_calendar" title="Hindu calendar">Hindu</a> <ul><li><a href="/wiki/Vikram_Samvat" title="Vikram Samvat">Vikram Samvat</a></li> <li><a href="/wiki/Indian_national_calendar" title="Indian national calendar">Saka</a></li></ul></li> <li><a href="/wiki/Hmong_calendar" title="Hmong calendar">Hmong</a></li> <li><a href="/wiki/Igbo_calendar" title="Igbo calendar">Igbo</a></li> <li><a href="/wiki/Iranian_calendars" title="Iranian calendars">Iranian</a> <ul><li><a href="/wiki/Jalali_calendar" title="Jalali calendar">Jalali</a> <ul><li>medieval</li></ul></li> <li><a href="/wiki/Zoroastrian_calendar" title="Zoroastrian calendar">Zoroastrian</a></li></ul></li> <li><a href="/wiki/Irish_calendar" title="Irish calendar">Irish</a> <ul><li>Gaelic</li></ul></li> <li><a href="/wiki/Islamic_calendar" title="Islamic calendar">Islamic</a> <ul><li><a href="/wiki/Fasli_calendar" title="Fasli calendar">Fasli</a></li> <li><a href="/wiki/Tabular_Islamic_calendar" title="Tabular Islamic calendar">Tabular</a></li></ul></li> <li><a href="/wiki/Vira_Nirvana_Samvat" title="Vira Nirvana Samvat">Jain</a></li> <li><a href="/wiki/Japanese_calendar" title="Japanese calendar">Japanese</a></li> <li><a href="/wiki/Javanese_calendar" title="Javanese calendar">Javanese</a></li> <li><a href="/wiki/Korean_calendar" title="Korean calendar">Korean</a> <ul><li><a href="/wiki/Juche_calendar" title="Juche calendar">Juche</a></li></ul></li> <li><a href="/wiki/Kurdish_calendar" title="Kurdish calendar">Kurdish</a></li> <li><a href="/wiki/Lithuanian_calendar" title="Lithuanian calendar">Lithuanian</a></li> <li><a href="/wiki/Tirhuta_Panchang" title="Tirhuta Panchang">Maithili</a></li> <li><a href="/wiki/Malayalam_calendar" title="Malayalam calendar">Malayalam</a></li> <li><a href="/wiki/Mandaean_calendar" title="Mandaean calendar">Mandaean</a></li> <li><a href="/wiki/Meitei_calendar" title="Meitei calendar">Manipuri (Meitei)</a></li> <li><a href="/wiki/Melanau_calendar" title="Melanau calendar">Melanau</a></li> <li><a href="/wiki/Mongolian_calendar" title="Mongolian calendar">Mongolian</a></li> <li>Nepal <ul><li><a href="/wiki/Nepal_Sambat" title="Nepal Sambat">Nepal Sambat</a></li> <li><a href="/wiki/Vikram_Samvat" title="Vikram Samvat">Vikram Samvat</a></li> <li><a href="/wiki/Yele_Sambat" title="Yele Sambat">Yele Sambat</a></li></ul></li> <li><a href="/wiki/Nisga%27a#Nisga’a_calendar/life" title="Nisga'a">Nisg̱a'a</a></li> <li><a href="/wiki/Odia_calendar" title="Odia calendar">Odia</a></li> <li><a href="/wiki/Punjabi_calendar" title="Punjabi calendar">Punjabi</a> <ul><li><a href="/wiki/Nanakshahi_calendar" title="Nanakshahi calendar">Nanakshahi</a></li></ul></li> <li><a href="/wiki/Romanian_calendar" title="Romanian calendar">Romanian</a></li> <li><a href="/wiki/Shona_calendar" title="Shona calendar">Shona</a></li> <li><a href="/wiki/Somali_calendar" title="Somali calendar">Somali</a></li> <li><a href="/wiki/Sotho_calendar" title="Sotho calendar">Sesotho</a></li> <li><a href="/wiki/Slavic_calendar" title="Slavic calendar">Slavic</a> <ul><li><a href="/wiki/Slavic_Native_Faith%27s_calendars_and_holidays" title="Slavic Native Faith's calendars and holidays">Slavic Native Faith</a></li> <li><a href="/wiki/Macedonian_months" title="Macedonian months">Macedonian</a></li></ul></li> <li><a href="/wiki/Tamil_calendar" title="Tamil calendar">Tamil</a></li> <li><a href="/wiki/Thai_calendar" title="Thai calendar">Thai</a> <ul><li><a href="/wiki/Thai_lunar_calendar" title="Thai lunar calendar">lunar</a></li> <li><a href="/wiki/Thai_solar_calendar" title="Thai solar calendar">solar</a></li></ul></li> <li><a href="/wiki/Tibetan_calendar" title="Tibetan calendar">Tibetan</a></li> <li><a href="/wiki/Tripuri_calendar" title="Tripuri calendar">Tripuri</a></li> <li><a href="/wiki/Tulu_calendar" title="Tulu calendar">Tulu</a></li> <li><a href="/wiki/Vietnamese_calendar" title="Vietnamese calendar">Vietnamese</a></li> <li><a href="/wiki/Wheel_of_the_Year" title="Wheel of the Year">Wicca</a></li> <li><a href="/wiki/Xhosa_calendar" title="Xhosa calendar">Xhosa</a></li> <li><a href="/wiki/Yoruba_calendar" title="Yoruba calendar">Yoruba</a></li> <li><a href="/wiki/Zulu_calendar" title="Zulu calendar">Zulu</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%;font-weight:normal;">Types</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/Runic_calendar" title="Runic calendar">Runic</a></li> <li><a href="/wiki/Mesoamerican_calendars" title="Mesoamerican calendars">Mesoamerican</a> <ul><li><a href="/wiki/Mesoamerican_Long_Count_calendar" title="Mesoamerican Long Count calendar">Long Count</a></li> <li><a href="/wiki/Calendar_round" class="mw-redirect" title="Calendar round">Calendar round</a></li></ul></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%;font-weight:normal;">Christian variants</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/Coptic_calendar" title="Coptic calendar">Coptic</a></li> <li><a href="/wiki/Ethiopian_calendar" title="Ethiopian calendar">Ethiopian and Eritrean</a></li> <li><a href="/wiki/Julian_calendar" title="Julian calendar">Julian</a> <ul><li><a href="/wiki/Revised_Julian_calendar" title="Revised Julian calendar">Revised</a></li></ul></li> <li><a href="/wiki/Liturgical_year" title="Liturgical year">Liturgical year</a> <ul><li><a href="/wiki/Eastern_Orthodox_liturgical_calendar" title="Eastern Orthodox liturgical calendar">Eastern Orthodox</a></li></ul></li> <li><a href="/wiki/Calendar_of_saints" title="Calendar of saints">Saints</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Historical</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/Pre-Islamic_Arabian_calendar" title="Pre-Islamic Arabian calendar">Arabian</a></li> <li><a href="/wiki/Attic_calendar" title="Attic calendar">Attic</a></li> <li><a href="/wiki/Aztec_calendar" title="Aztec calendar">Aztec</a> <ul><li><a href="/wiki/T%C5%8Dnalp%C5%8Dhualli" title="Tōnalpōhualli">Tōnalpōhualli</a></li> <li><a href="/wiki/Xiuhp%C5%8Dhualli" title="Xiuhpōhualli">Xiuhpōhualli</a></li></ul></li> <li><a href="/wiki/Babylonian_calendar" title="Babylonian calendar">Babylonian</a></li> <li><a href="/wiki/Bulgar_calendar" title="Bulgar calendar">Bulgar</a></li> <li><a href="/wiki/Byzantine_calendar" title="Byzantine calendar">Byzantine</a></li> <li><a href="/wiki/Cappadocian_calendar" title="Cappadocian calendar">Cappadocian</a></li> <li><a href="/wiki/Celtic_calendar" title="Celtic calendar">Celtic</a></li> <li><a href="/wiki/Cham_calendar" title="Cham calendar">Cham</a></li> <li><a href="/wiki/Chula_Sakarat" title="Chula Sakarat">Culāsakaraj</a></li> <li><a href="/wiki/Coligny_calendar" title="Coligny calendar">Coligny</a></li> <li><a href="/wiki/Egyptian_calendar" title="Egyptian calendar">Egyptian</a></li> <li><a href="/wiki/Enoch_calendar" title="Enoch calendar">Enoch</a></li> <li><a href="/wiki/Florentine_calendar" title="Florentine calendar">Florentine</a></li> <li><a href="/wiki/French_Republican_calendar" title="French Republican calendar">French Republican</a></li> <li><a href="/wiki/Germanic_calendar" class="mw-redirect" title="Germanic calendar">Germanic</a></li> <li><a href="/wiki/Ancient_Greek_calendars" title="Ancient Greek calendars">Greek</a></li> <li><a href="/wiki/Hindu_calendar" title="Hindu calendar">Hindu</a></li> <li><a href="/wiki/Inca_calendar" class="mw-redirect" title="Inca calendar">Inca</a></li> <li><a href="/wiki/Ancient_Macedonian_calendar" title="Ancient Macedonian calendar">Macedonian</a></li> <li><a href="/wiki/Maya_calendar" title="Maya calendar">Maya</a> <ul><li><a href="/wiki/Haab%CA%BC" title="Haabʼ">Haabʼ</a></li> <li><a href="/wiki/Tzolk%CA%BCin" title="Tzolkʼin">Tzolkʼin</a></li></ul></li> <li><a href="/wiki/Muisca_calendar" title="Muisca calendar">Muisca</a></li> <li><a href="/wiki/Pentecontad_calendar" title="Pentecontad calendar">Pentecontad</a></li> <li><a href="/wiki/Pisan_calendar" title="Pisan calendar">Pisan</a></li> <li><a href="/wiki/Qumran_calendrical_texts" title="Qumran calendrical texts">Qumran</a></li> <li><a href="/wiki/Rapa_Nui_calendar" title="Rapa Nui calendar">Rapa Nui</a></li> <li><a href="/wiki/Roman_calendar" title="Roman calendar">Roman</a></li> <li><a href="/wiki/Rumi_calendar" title="Rumi calendar"><i>Rumi</i></a></li> <li><a href="/wiki/Sexagenary_cycle" title="Sexagenary cycle">Sexagenary</a></li> <li><a href="/wiki/Soviet_calendar" title="Soviet calendar">Soviet</a></li> <li><a href="/wiki/Swedish_calendar" title="Swedish calendar">Swedish</a></li> <li><a href="/wiki/2002_renaming_of_Turkmen_months_and_days_of_week" title="2002 renaming of Turkmen months and days of week">Turkmen</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">By specialty</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/Holocene_calendar" title="Holocene calendar">Holocene</a> <ul><li>anthropological</li></ul></li> <li><a href="/wiki/Proleptic_Gregorian_calendar" title="Proleptic Gregorian calendar">Proleptic Gregorian</a> / <a href="/wiki/Proleptic_Julian_calendar" title="Proleptic Julian calendar">Proleptic Julian</a> <ul><li>historiographical</li></ul></li> <li><a href="/wiki/Darian_calendar" title="Darian calendar">Darian</a> <ul><li>Martian</li></ul></li> <li><a href="/wiki/Dreamspell" title="Dreamspell">Dreamspell</a> <ul><li>New Age</li></ul></li> <li><a href="/wiki/Discordian_calendar" title="Discordian calendar">Discordian</a></li> <li><a href="/wiki/%27Pataphysics#Pataphysical_calendar" title="'Pataphysics">'Pataphysical</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Calendar_reform" title="Calendar reform">Reform proposals</a></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/Hanke%E2%80%93Henry_Permanent_Calendar" title="Hanke–Henry Permanent Calendar">Hanke–Henry Permanent</a></li> <li><a href="/wiki/International_Fixed_Calendar" title="International Fixed Calendar">International Fixed</a></li> <li><a href="/wiki/Pax_Calendar" title="Pax Calendar">Pax</a></li> <li><a href="/wiki/Positivist_calendar" title="Positivist calendar">Positivist</a></li> <li><a href="/wiki/Symmetry454" title="Symmetry454">Symmetry454</a></li> <li><a href="/wiki/World_Calendar" title="World Calendar">World</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><div style="display: inline-block; line-height: 1.2em; padding: .1em 0;">Displays and<br />applications</div></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/Calendaring_software" class="mw-redirect" title="Calendaring software">Electronic</a></li> <li><a class="mw-selflink selflink">Perpetual</a></li> <li><a href="/wiki/Calendar_(stationery)" title="Calendar (stationery)">Wall</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><div style="display: inline-block; line-height: 1.2em; padding: .1em 0;">Year naming<br />and numbering</div></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%;font-weight:normal;">Terminology</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/Calendar_era" title="Calendar era">Era</a></li> <li><a href="/wiki/Epoch" title="Epoch">Epoch</a></li> <li><a href="/wiki/Leap_year" title="Leap year">Leap year</a></li> <li><a href="/wiki/New_Year" title="New Year">New Year</a></li> <li><a href="/wiki/Regnal_name" title="Regnal name">Regnal name</a></li> <li><a href="/wiki/Regnal_year" title="Regnal year">Regnal year</a></li> <li><a href="/wiki/Year_zero" title="Year zero">Year zero</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%;font-weight:normal;">Systems</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/Ab_urbe_condita" title="Ab urbe condita">Ab urbe condita</a></li> <li><a href="/wiki/Anka_year" title="Anka year">Anka year</a></li> <li><a href="/wiki/Anno_Domini" title="Anno Domini">Anno Domini</a>/<a href="/wiki/Common_Era" title="Common Era">Common Era</a></li> <li><a href="/wiki/Anno_Lucis" title="Anno Lucis">Anno Lucis</a></li> <li><a href="/wiki/Era_of_the_Martyrs" title="Era of the Martyrs">Anno Martyrum</a></li> <li><a href="/wiki/Anno_Mundi" title="Anno Mundi">Anno Mundi</a></li> <li><a href="/wiki/Eponym_dating_system" title="Eponym dating system">Assyrian</a></li> <li><a href="/wiki/Before_Present" title="Before Present">Before Present</a></li> <li><a href="/wiki/Chinese_era_name" title="Chinese era name">Chinese Imperial</a></li> <li><a href="/wiki/Republic_of_China_calendar" title="Republic of China calendar">Chinese Minguo</a></li> <li><a href="/wiki/Regnal_years_of_English_and_British_monarchs" title="Regnal years of English and British monarchs">English and British regnal year</a></li> <li><a href="/wiki/Hijri_year" title="Hijri year">Hijri year</a></li> <li><a href="/wiki/Holocene_calendar" title="Holocene calendar">Human (Holocene)</a></li> <li><a href="/wiki/Japanese_era_name" title="Japanese era name">Japanese</a></li> <li><a href="/wiki/Korean_era_name" title="Korean era name">Korean</a></li> <li><a href="/wiki/Nirayana_system" title="Nirayana system">Nirayana system</a></li> <li><a href="/wiki/Seleucid_era" title="Seleucid era">Seleucid</a></li> <li><a href="/wiki/Spanish_era" title="Spanish era">Spanish</a></li> <li><a href="/wiki/Yuga" title="Yuga">Yugas</a> <ul><li><a href="/wiki/Satya_Yuga" title="Satya Yuga">Satya</a></li> <li><a href="/wiki/Treta_Yuga" title="Treta Yuga">Treta</a></li> <li><a href="/wiki/Dvapara_Yuga" title="Dvapara Yuga">Dvapara</a></li> <li><a href="/wiki/Kali_Yuga" title="Kali Yuga">Kali</a></li></ul></li> <li><a href="/wiki/Vietnamese_era_name" title="Vietnamese era name">Vietnamese</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Fictional</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/Discworld_(world)#Calendar" title="Discworld (world)">Discworld</a> (<i><a href="/wiki/Discworld" title="Discworld">Discworld</a></i>)</li> <li><a href="/wiki/Flanaess#Calendar" class="mw-redirect" title="Flanaess">Greyhawk</a> (<i><a href="/wiki/Dungeons_%26_Dragons" title="Dungeons & Dragons">Dungeons & Dragons</a></i>)</li> <li><a href="/wiki/Middle-earth_calendar" class="mw-redirect" title="Middle-earth calendar">Middle-earth</a> (<i><a href="/wiki/The_Lord_of_the_Rings" title="The Lord of the Rings">The Lord of the Rings</a></i>)</li> <li><a href="/wiki/Stardate" title="Stardate">Stardate</a> (<i><a href="/wiki/Star_Trek" title="Star Trek">Star Trek</a></i>)</li></ul> </div></td></tr><tr><td class="navbox-abovebelow hlist" colspan="2"><div> <ul><li><span class="noviewer" typeof="mw:File"><span title="List-Class article"><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/d/db/Symbol_list_class.svg/16px-Symbol_list_class.svg.png" decoding="async" width="16" height="16" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/d/db/Symbol_list_class.svg/23px-Symbol_list_class.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/d/db/Symbol_list_class.svg/31px-Symbol_list_class.svg.png 2x" data-file-width="180" data-file-height="185" /></span></span> <a href="/wiki/List_of_calendars" title="List of calendars">List of calendars</a></li> <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:Calendars" title="Category:Calendars">Category</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 authority-control" aria-label="Navbox" style="padding:3px"><table class="nowraplinks hlist navbox-inner" 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