Wikipedia:Naming conventions (numbers and dates)

Manual of Style (dates and numbers) gives the general principles of how Wikipedia deals with the representation of numbers and dates.

This present naming conventions guideline concentrates on the aspect of how numbers and dates are represented in article titles, that is the names of the articles where the content is (as opposed to redirect pages that also allow non-standardized article titles).

The approach of this guideline is listing recommendations by article content type.

Articles on years, articles on numbers, article names containing non-date numbers
Pages with numeric titles 151 and above usually represent an article about a calendar year in the Common Era, up till several decades in the future (see User:Crouch, Swale/Year DAB for exceptions). Such articles give an overview, in the form of a list, of the major events that took place (or are planned to take place) in that year. In general the use of number-only page names should only be used for "Year in Review" entries.

By community consensus, an article title that is a number in Arabic numerals 1 through 100 is about the number (or hosts a DAB), not the year. (This has since been extended to numbers up to 150, and a few other specific examples like 911.) For these years AD, the format is "AD ", for example AD 100. For years BCE, the format is " BC", for example 44 BC.

Some numbers that don't indicate a year have a specific meaning, so an additional qualifier or disambiguation technique is needed:
 * An article on a number has the bracketed qualifier (number) added to its article title in case of ambiguity, e.g. 103 (number)
 * Other:
 * 36 (film), not 36 which is ambiguous;
 * Intel 80386, not 386 (the year the Northern Wei dynasty began to rule China);
 * Form 1040, not 1040 (the year Macbeth became King of Scotland);
 * Nineteen Eighty-Four for the George Orwell novel, not 1984 (the year Marvin Gaye died);
 * 4711 for the Eau de Cologne (out of the "several decades in the future" range).

Note that numbers in Roman numerals are usually pages that redirect to: Unless, of course, the letters, not read as Roman numerals, compose a word with another meaning, e.g. MIX.
 * the related number article for lower numbers
 * the related year article for higher numbers, e.g. MMVI redirects to 2006

There is a unicode range of characters that is specifically used for Roman numerals, for example "Ⅰ" (0x2160) and "ⅰ" (0x2170) – such (individual) characters are redirect pages to the the above-linked section about Roman numerals in Unicode. For other uses it is discouraged to use these characters in Wikipedia article page names. Note also that no automatic case conversion to upper case takes place when these characters are used as the first character of a Wikipedia page name (in other words: "Ⅰ" and "ⅰ" are two different redirect pages).

See also: Manual of Style (dates and numbers).

Days

 * All days of a year cycle have an article in the format " ", e.g. February 27 February 27 which displays as February 27, depending on your date preferences.
 * Additionally, days from some recent years (currently: 2003–2005) have an article with a title in the format ", ", e.g. February 27, 2003 – these articles on a specific day of a specific year can be reached from the " " articles via the This date in recent years template. An example of this template is displayed on the right.
 * Of course there are also the articles Sunday to Saturday, without numbers in the article name.

Months

 * Articles January to December;
 * For months in particular years the format is " ", e.g. April 2006

Decades

 * Format: " s (BC)", e.g. 1970s, 40s BC. For avoidance of ambiguity, (decade) is added as a disambiguator for the first decade of a century (or the last decade of a century BC), e.g. 1800s (decade), to which for instance 1800–1809 redirects. 1800s is a disambiguation page.

Centuries

 * Format: " th century (BC)", e.g. 3rd century BC (see: Category:Centuries)

Millennia

 * Format: " th millennium (BC)", e.g. 2nd millennium (see Category:Millennia)

Article titles consisting exclusively of numbers and separators
Article titles consisting exclusively of both arabic numerals and separators (like hyphens) are discouraged for content pages. They should be either redirects or disambiguation pages, for example:
 * 1914-1918 redirects to World War I.
 * 1/2 is a disambiguation page
 * 1978–1990 (Go-Betweens album) — adding parenthical disambiguator for content page

Events recurring at regular intervals
There are many events that repeat on a regular or semi-regular basis, such as the Summer Olympics or the U.S. presidential elections. For important events, we will want a separate article for every time the event was held. For such events, one question that arises is: "What's the best way to disambiguate this series of articles?".

Year in front
Example: 2000 Summer Olympics

While the date is up front, this gives a maybe undue focus to the year, rather than to the event; this format is however widely used, so acceptable as Wikipedia page name format.

Year at the end, with comma
In general, use of punctuation marks in article names is discouraged. A request for comment closed in November 2018 deprecated this format in articles about elections. The preferred format for elections is "  election". As such United States presidential election, 2000 redirects to 2000 United States presidential election. See Naming conventions (government and legislation).

Without date
Also numerical disambiguation for recurring events exists, if this is a usual and generally recognisable way to indicate the event. E.g. Super Bowl → from Super Bowl I (1967) to Super Bowl XLV (2011), etc.

Other events
For events that recur at non-regular intervals, for instance Ecumenical councils, the articles on the individual events usually avoid a date indication, but are numbered/characterised otherwise (e.g. place of event, combined with numerical), for instance: Fourth Council of the Lateran; First Council of Lyon; Second Council of Lyon; Council of Vienne – similarly for Crusades: First Crusade, Second Crusade, etc... Note, however, that exceptions to the rule of avoiding dates are applied according to established practice, for instance: Crusade of 1101 (minor crusade, not numbered, and generally indicated by the year it occurred).

Note that for numbering usually a text version of the numbers is used for these types of events, or (exceptionally) Roman numerals, if that is the most established practice (e.g. World War I, World War II).

If a time indicator is used in the title of an article on an event that doesn't recur at regular intervals (or didn't recur at all) there's no "standard format" for the representation of the time indicator, so there is for instance: Crisis of the Third Century; German Crusade, 1096 (one of the developments of the First Crusade); etc. The format of the date depends, in these cases, from established practice in history books and the like. In general, however, abbreviations for years or months are usually avoided (e.g., Jan. '68 → January 1968) unless when there's a clear established practice in reliable sources to do otherwise (e.g. May 68, different from May 1968); for centuries numerals are given in text, capitalised (e.g., Crisis of the 3rd century → Crisis of the Third Century)

For disasters (see WikiProject Disaster management), the recommended format is "  ". Examples: 2006 New York City plane crash, 1700 Cascadia earthquake. This is only a "soft" recommendation, if no other more appropriate name is available. Counter-examples include Space Shuttle Challenger disaster, Pan Am Flight 103, Minoan eruption, and Kyrill (storm).

Article titles containing an indication of duration
As for events that don't recur on (semi-)regular intervals, article titles containing a reference to a time period (not a date) are not bound by strict rules, apart from using the most common name. However, generally, in these cases numbers are written in text, and abbreviations are avoided. Some examples:
 * Four-year plan
 * Hundred Years' War

Articles on people
For ordinals applied in titles of articles on persons see Naming conventions (people) and several culture-specific naming conventions like Naming conventions (royalty and nobility), Naming conventions (clergy), etc..., and examples in, for instance, Category:Pharaohs and subcategories.

Apart from such ordinals, it is recommended to avoid any type of numbers in the title of an article that is about a single person, see Naming conventions (people):"[...] Try to avoid abbreviations or anything capitalised or containing numbers (apart from where more specific guidelines specify particular exceptions to that) [...]" A notable exception to this is contained in Naming conventions (ancient Romans): Article titles for the biographies of ancient Romans often need to be disambiguated. The Romans used a limited number of names, and family names were carried on for generations (see Category:Prosopography of ancient Rome, and prosopographical lists such as Lucius Calpurnius Piso Frugi for a specific example). Article titles may be disambiguated through an epithet or agnomen commonly used in English or by a parenthetical word or phrase: Antoninus Pius, Constantine the Great (an anomaly among article titles for emperors), Gaius Papirius (Pontifex Maximus). Other forms of disambiguation include:
 * Highest office. Men who had a public career should usually be distinguished by the highest office held: Lucius Cornelius Scipio (praetor).
 * If more than one man by this name held the same office, add a date for disambiguation: Quintus Fulvius Flaccus (consul 237 BC). If a man held the office more than once, use only the year of his first term.
 * Notability. A Roman who held no office may be distinguished by most notable activity, occupation, or role: Gaius (jurist), Lucius Calpurnius Piso Frugi (usurper).
 * This form of disambiguation may be used instead of highest office if the figure achieved greater notability in another area: Marcus Antonius (orator).
 * "General" is usually too vague to disambiguate Roman men, as the English word represents a broad category of military commands and titles among the Romans, and such commands were common among the ruling elite.
 * Personal relationship. If a person's primary notability is a familial or other personal relationship to a better-known person, it may be acceptable to disambiguate accordingly: Gnaeus Pompeius Magnus (husband of Claudia Antonia).

Various examples
Examples illustrate the various ways dates and numbers can show up in article names.
 * Straße des 17. Juni: Name of a street in Berlin. The name of this street refers to a date ("17th of June") – the whole is kept in German, while that's the way the street is referred to, also in English. Note that the point after the number 17 is the German way of writing what in English translates to "th" (in German this point is pronounced as "ten").
 * October Revolution: Traditional name for this stage of the Russian revolution—although it took place in November according to Gregorian calendar: both the October 25 and the November 7 article mention the event, the first according to Julian calendar, the second according to Gregorian calendar.
 * The Excursions of Mr. Brouček to the Moon and to the 15th Century: Opera by Janáček – "Century" with a capital and "15th" (not "Fifteenth"), according to Naming conventions (operas).
 * 44 Duos for Two Violins – String Quartet No. 10 (Beethoven) –  1. X. 1905 –  Minute Waltz –  etc.: Numbering and naming of compositions according to Naming conventions (music). "1. X. 1905" is nothing more than a date, 1905-10-01, which happens to be the name of a musical composition—but since, as a date, "1. X. 1905" is in a format not similar to any notation format that is used in English, it doesn't need to be disambiguated from calendar-related articles.
 * E17: Letter/number combination with various meanings, so this leads to a disambiguation page.
 * HMS Tiara (P351) – A-B Helicopters A/W 95 –  etc.: Several vehicle names contain combinations of numbers and/or letters, see Naming conventions (ships), Naming conventions (aircraft), etc.
 * XIII: Disambiguation page from which, for example, 13 (number) and XIII (comic) can be reached.
 * Titanic (1953 film) – 36 (film) –  Ocean's Twelve –  etc.: Film titles according to Naming conventions (films).
 * Twenty Thousand Leagues Under the Sea – Paris in the Twentieth Century –  etc.: Titles of books (and other publications) use the conventional way the (English version) of the publication's title is printed. See Naming conventions (books).
 * Queen Elizabeth II – RMS Queen Elizabeth 2: Both are redirect pages, the first to the queen ("II" used as ordinal in the name of a royal person), the second to the ship ("2" used as a number, in a ship's name).
 * September 11 attacks : a.k.a. 9/11 – several options for the name of this page were considered (and the page has a high number of redirects pointing towards it); however, the final choice of the page name does not necessarily set a "standard" for formatting page names containing a date.
 * Triple J Hottest 100, 1989; Triple J Hottest 100, 1990; etc.: An annually compiled list of each year's most popular songs, as determined by listeners of the Australian radio station Triple J. The year in question goes on the end after a comma.