Template:Start date and age/doc

This is a documentation subpage for Template:Start date and age.
It contains usage information, categories and other content that is not part of the original template page.

This template is used on approximately 110,000 pages.
To avoid major disruption and server load, any changes should be tested in the template's /sandbox or /testcases subpages, or in your own user subpage. The tested changes can be added to this page in a single edit. Consider discussing changes on the talk page before implementing them.

The {{Start date and age}} template displays the date that an event or entity started or was created. It also includes a duplicate, machine-readable date in the ISO 8601 format (which is hidden by CSS), for use inside other templates which emit microformats. The hidden date degrades gracefully when CSS is not available.

Usage

Common usage: {{Start date and age|yyyy|mm|dd}} to display formatted as:; March 25, 2010; 14 years ago (2010-03-25); {{Start date and age|yyyy|mm|dd|df=yes}} to display formatted as:; 25 March 2010; 14 years ago (2010-03-25)

Full syntax: {{Start date and age|yyyy|mm|dd|df=yes|p=yes|br=yes}} to display formatted as:; 25 March 2010
(14 years ago) (2010-03-25)

Parameters

Parameter	Status	Description
1	required	A four-digit number indicating the year.
2	optional	A number between 1 and 12 indicating the month (leading zeros in the number are ignored). The month may also be specified as a name or abbreviation (e.g. "August" or "Aug").
3	optional	A number between 1 and 31 indicating the day of the month (leading zeros in the number are ignored).
df=	optional	If the parameter df equals yes, y, or 1, the date will be displayed in DMY format: 4 March 2010. When this parameter is not included or set to some other value, the date will be displayed in MDY format: March 4, 2010.
p= paren=	optional	If the parameter p or paren equals yes, y, or 1, the age will be displayed within parentheses. When this parameter is not included or set to some other value, the date and age are separated by a semicolon and a breaking space.
br=	optional	If the parameter br equals yes, y, or 1, a line break will be inserted between the date and the age. When this parameter is not included or set to some other value, a breaking space will be inserted between the date and the age. This does not change the separating characters between the date and age which are either a semicolon (default setting) or parentheses (if p=yes).
end=	optional	This template includes hidden microformat `<span class="bday dtstart published updated">`, similar to Template:Start date. If the parameter end equals yes, y, or 1, the template will instead use `<span class="dtend">`, similar to Template:End date. This parameter is used by Template:End date and age. For more details, see Wikipedia:WikiProject Microformats.

"df" (day first) and "mf" (month first)

The default output of this template is to display the month before the day (MDY). This default may not be appropriate for articles about events or entities in parts of the world where dates are commonly given with the day preceding the month (DMY). To display the day first, assign the df parameter a value of yes, y, or 1 (e.g. df=yes).

If the default format is preferred, the parameter df may be used with value of no, n, or 0 (e.g. df=no). These values can assist bots or other automated processing to detect the intended date format; omitting the df parameter may lead an editor or bot to change the format to an unintended value.

The preference to display the month first may also be indicated via the parameter mf (e.g. mf=yes). While not actually used by the template, this is another method of indicating that the default format is intended. Do not specify both "df" and "mf" parameters in the same use of the template.

Examples

Default separator: semicolon

Syntax	Result
Full date (year, month, day)
`{{Start date and age\|2010\|01\|02}}`	January 2, 2010; 14 years ago (2010-01-02)
`{{Start date and age\|2008\|Jan\|09\|df=no}}`	January 9, 2008; 16 years ago (2008-01-09)
`{{Start date and age\|2003\|January\|05\|mf=yes}}`	January 5, 2003; 21 years ago (2003-01-05)
`{{Start date and age\|2010\|1\|2\|df=yes}}`	2 January 2010; 14 years ago (2010-01-02)
`{{Start date and age\|2008\|Jan\|9\|df=y}}`	9 January 2008; 16 years ago (2008-01-09)
`{{Start date and age\|2003\|January\|5\|df=1}}`	5 January 2003; 21 years ago (2003-01-05)
100 days ago: `{{Start date and age\|2024\|9\|13}}`	September 13, 2024; 3 months ago (2024-09-13)
Yesterday: `{{Start date and age\|2024\|12\|21}}`	December 21, 2024; 1 day ago (2024-12-21)
Today: `{{Start date and age\|2024\|12\|22}}`	December 22, 2024; 0 days ago (2024-12-22)
Year and month
`{{Start date and age\|2001\|9}}`	September 2001; 23 years ago (2001-09)
`{{Start date and age\|2002\|09}}`	September 2002; 22 years ago (2002-09)
`{{Start date and age\|2003\|Sep}}`	September 2003; 21 years ago (2003-09)
`{{Start date and age\|2004\|September}}`	September 2004; 20 years ago (2004-09)
Year only
`{{Start date and age\|2005}}`	2005; 19 years ago (2005)

Optional separator: parentheses

Syntax	Result
Full date (year, month, day)
`{{Start date and age\|2003\|02\|15\|p=yes}}`	February 15, 2003 (21 years ago) (2003-02-15)
`{{Start date and age\|2003\|02\|15\|df=y\|p=y}}`	15 February 2003 (21 years ago) (2003-02-15)
Year and month
`{{Start date and age\|2003\|02\|p=1}}`	February 2003 (21 years ago) (2003-02)
Year only
`{{Start date and age\|2003\|paren=yes}}`	2003 (21 years ago) (2003)

Line break with semicolon

Syntax	Result
Full date (year, month, day)
`{{Start date and age\|2003\|02\|15\|br=yes}}`	February 15, 2003; 21 years ago (2003-02-15)
`{{Start date and age\|2003\|02\|15\|df=y\|br=y}}`	15 February 2003; 21 years ago (2003-02-15)
Year and month
`{{Start date and age\|2003\|02\|br=1}}`	February 2003; 21 years ago (2003-02)
Year only
`{{Start date and age\|2003\|br=yes}}`	2003; 21 years ago (2003)

Line break with parentheses

Syntax	Result
Full date (year, month, day)
`{{Start date and age\|2003\|02\|15\|p=yes\|br=yes}}`	February 15, 2003 (21 years ago) (2003-02-15)
`{{Start date and age\|2003\|02\|15\|df=y\|p=y\|br=y}}`	15 February 2003 (21 years ago) (2003-02-15)
Year and month
`{{Start date and age\|2003\|02\|p=1\|br=1}}`	February 2003 (21 years ago) (2003-02)
Year only
`{{Start date and age\|2003\|paren=yes\|br=yes}}`	2003 (21 years ago) (2003)

Use in microformats

This template also returns the date, hidden by CSS, in the ISO 8601 format needed by one or more of the following microformats:

hAtom (class="updated")
hAudio (class="published")
hCalendar (class="dtstart")
hCard (class="bday")

usually, but not always, within infobox or similar templates, or tables.

Its use in hCard is for organizations, venues and similar; use {{Birth date}} or {{Birth date and age}} for people.

Similarly, {{End date}} returns the date as hCalendar's (class="dtend").

See the microformats project for further details.

Limitation

This template has no provision to deal with a date in a non-Gregorian calendar. Also, ISO 8601 requires mutual agreement among those exchanging information before using years outside the range 1583–9999 CE. Therefore, use of this template for non-Gregorian dates or dates outside that range constitutes a false claim of conformance to the ISO 8601 standard.

Any editor encountering such usage should change the date to plain text with no template; or if not confident in doing so, raise the matter on this template's talk page.

Example

{{Start date and age|2016|12|31}} → December 31, 2016; 7 years ago

December&nbsp;31, 2016<span class="noprint">&#059;&#032;7 years ago</span><span style="display:none">&#160;(<span class="bday dtstart published updated">2016-12-31</span>)</span>

Usage in articles

This template is most often used in infoboxes in articles about buildings or organizations, identifying when they were started/founded/opened or dissolved/ended/closed.

It has also been used for naval ships to indicate their commissioned age, however several Wikipedia editors have reverted such edits. Use of this template in ship articles is therefore not recommended.

Supporting templates

Template:MONTHNAME – display name of month for a given number 1 (January) through 12 (December).
Template:Time ago – display number of days, months, or years ago (for dates given as |yyyy|mm|dd).
Template:Years or months ago – display number of months or years ago (for dates given as |yyyy|mm or |yyyy).
Template:Yesno – allows optional formatting parameters to accept values other than "yes" (such as "y" or "1").

Template	Description / use
{{BirthDeathAge}}	Combines functions of {{birth date}}, {{birth-date}}, {{birth date and age}}, {{birth year and age}}, {{death date}}, {{death-date}}, {{death date and age}} and {{death year and age}}.
{{birth date}}	To display a birth date and related hidden metadata.
{{birth-date}}
{{birth date and age}}	{{birth date}} with suffix "(age N)".
{{birth date and age2}}	{{birth date and age}} plus age as of a specified date.
{{birth-date and age}}	As {{birth date and age}} but accepts dates in text form ("15 June 1950", "June 15, 1950", "June 1950", etc).
{{birth year and age}}	Year of birth and approximate age.
{{birth based on age as of date}}	To display approximate birth year and current age given a particular date (e.g. when a dated reference mentions the age of a person).
{{birth based on age at death}}	To display approximate birth year based on age at death.

Template	Description / use
{{death date}}	To display a death date and related hidden metadata.
{{death-date}}
{{death date and age}}	{{death date}} with suffix "(aged N)". Also called with {{event date and age}}
{{death-date and age}}	As {{death date and age}} but accepts dates in text form ("15 June 1950", "June 15, 1950", "June 1950", etc).
{{death date and given age}}	To display a death date and specified age.
{{death year and age}}	To display a year of and approximate age at death.

Age only

Template	Description / use
{{age in years, months, weeks and days}}	Number of complete years, months, weeks and days between two dates.
{{age in years, months and days}}	Number of complete years, months and days between two dates.
{{age in years and months}}	Number of complete years and remaining months between two dates.
{{age in years and days}}	Number of complete years and remaining days between two dates.
{{age in years and days nts}}	{{age in years and days}} with output formatted for use in sortable tables.
{{age in decimal years}}	Number of years between two dates, rounded to the specified number of decimal places.
{{age in years}}	Number of years between two dates.
{{age in years nts}}	{{age in years}} with output formatted for use in sortable tables.
{{age in months}}	Number of months between two dates.
{{age in weeks and days}}	Number of weeks and days between two dates.
{{age in weeks}}	Number of weeks between two dates.
{{age in days}}	Age in days between two dates.
{{age in days nts}}	{{age in days}} with output formatted for use in sortable tables.

Template	Description / use
{{age}}	Age based on number of complete years between two dates.
{{age nts}}	{{age}} with output formatted for use in sortable tables.
{{age as of date}}	Current age (in years) from a known age at a specified date.
{{age for infant}}	Current age for infant: months and days up to one year, years and months up to three years, and years beyond.

Start / end dates

Template	Description / use
{{start date}} / {{end date}}
{{start-date}} / {{end-date}}
{{start date and age}}
{{end date and age}}

Miscellaneous

Template	Description / use
{{OldStyleDate}}	Dates pre-1584 in Julian calendar
{{Unidentified for}}
{{Missing for}}

TemplateData

TemplateData documentation used by VisualEditor and other tools

Click here to see a monthly parameter usage report for this template based on this TemplateData.

TemplateData for Start date and age

The Start date and age template displays the date that an event or entity started or was created.

Template parameters
Parameter		Description	Type	Status
Year	`1`	A four-digit number indicating the year Example 2017	Number	required
Month	`2`	A number between 1 and 12 indicating the month Example 12	Number	suggested
Day	`3`	A number between 1 and 31 indicating the day of the month Example 31	Number	suggested
Display date first	`df`	If the parameter df equals yes, y, or 1, the date will be displayed in DMY format: 4 March 2010. When this parameter is not included or set to some other value, the date will be displayed in MDY format: March 4, 2010. Default no Example no	Boolean	optional
Display with parentheses	`paren` `p`	If the parameter p or paren equals yes, y, or 1, the age will be displayed within parentheses. When this parameter is not included or set to some other value, the date and age are separated by a semicolon and a breaking space. Default no Example yes	Boolean	optional
Line break between date and age	`br`	If the parameter br equals yes, y, or 1, a line break will be inserted between the date and the age. When this parameter is not included or set to some other value, a breaking space will be inserted between the date and the age. This does not change the separating characters between the date and age which are either a semicolon (default setting) or parentheses (if paren=yes). Default no Example yes	Boolean	optional
Use microformat for end date	`end`	This template includes hidden microformat <span class="bday dtstart published updated">, similar to Template:Start date. If the parameter end equals yes, y, or 1, the template will instead use <span class="dtend">, similar to Template:End date. This parameter is used by Template:End date and age. For more details, see Wikipedia:WikiProject Microformats. Default no Example yes	Boolean	optional