From Wikipedia, the free encyclopedia
(Redirected from Help:Date math)

Date math on Wikipedia is done with variables, templates and the #time parser function.

In articles, it is almost always preferred to specify a specific static date for a statement or event rather than an automatically generated date. Wikipedia:As of describes how to properly specify such dates.

Current date and time

Built-in variables Templates based on them What you see Comments
{{CURRENTTIMESTAMP}} 20240603142349
{{CURRENTYEAR}} 2024
{{ UTC}} 2024-06-03 14:23  UTC also uses {{CURRENTMONTH}} {{CURRENTDAY2}} {{CURRENTTIME}}
{{ CURRENTDATE}} 14:23, Monday, June 3, 2024 ( UTC) also uses {{CURRENTTIME}} {{CURRENTDAYNAME}} {{CURRENTMONTHNAME}} {{CURRENTDAY}}
{{ CURRENTJULIANDAY}} 2460465.0998727 current Julian day also uses {{CURRENTMONTH}} {{CURRENTDAY}} {{CURRENTHOUR}} {{ CURRENTMINUTE}} {{ CURRENTSECOND}}
{{CURRENTMONTH}} 06
{{ CURRENTMNTH}} 6 trims leading zero
{{CURRENTMONTHNAME}} June
{{ Month+1}} July
{{ Month-1}} May
{{ Month-2}} April
{{CURRENTDAY}} 3 day of month
{{CURRENTDOW}} 1 day of week
{{#time:l|-1 day}} Sunday
{{#time:l}} Monday
{{#time:l|+1 day}} Tuesday
Any variable or template with a resolution of smaller than one day should not be placed in articles. These variables only indicate when the article was parsed and cached; they may lag by many hours or even days compared to the time the page is viewed.
{{CURRENTTIME}} 14:23
{{CURRENTHOUR}} 14
{{#time:H|+1 hour}} 15
{{ Current hour}} 14 trims leading zero
{{#time:i}} 23
{{ CURRENTMINUTE}} 23
{{ Current minute}} 23 trims leading zero
{{#time:s}} 49
{{ CURRENTSECOND}} 49

Computed date and time

Template name Usage Output Comment
{{ Ordinal date}} {{Ordinal date|year=2007|month=03|day=15}} 74 returns ordinal date (day of year)
{{Ordinal date|year=2008|month=03|day=15}} 75 +1 due to leap year in 2008
{{ WEEKDAY}} {{WEEKDAY|2009|08|25}} 1 returns day of week
{{WEEKDAYNAME|{{WEEKDAY|2009|08|25}}}} Tuesday
{{ JULIANDAY}} {{JULIANDAY|2009|08|25}} 2455069
{{WEEKDAYNAME|{{JULIANDAY|2009|08|25}}}} Tuesday Note: 2455069 mod 7 = 1
{{JULIANDAY|{{CURRENTYEAR}}|{{CURRENTMONTH}}|{{CURRENTDAY}}}} 2460465 Nesting templates to get the value of the current Julian day with no decimal portion. Useful for date math between a set point and the current date.
{{ JULIANDAY.TIMESTAMP}} {{JULIANDAY.TIMESTAMP|2455069}} 20090825120000 same format as {{CURRENTTIMESTAMP}}
{{#time:D Y-m-d|{{JULIANDAY.TIMESTAMP|2455069}}}} Tue 2009-08-25

Julian dates or day numbers can be used for date calculations. A simple example follows:

  1. 90 days from 25 December 2006 is: 25 March 2007
    • Code: {{#time:j F Y|{{JULIANDAY.TIMESTAMP|{{JULIANDAY|2006|12|25}}+90}}}}
  2. 90 days from 25 December 2007 is: 24 March 2008 (1 day less than first example due to leap year in 2008)
    • Code: {{#time:j F Y|{{JULIANDAY.TIMESTAMP|{{JULIANDAY|2007|12|25}}+90}}}}

Fancy stuff

Today is
3
Tomorrow
4
{{ today cell}} {{ tomorrow cell}}

See also