Editing Template:Birth date and age/doc

This template will return a living person's date of birth and age. Using this template rather than simply inserting the date into articles allows for the inclusion of hidden metadata about the date. This metadata can be used by web browsers and other software tools to extract the details, and display them using some other website or mapping tool, index, or search them.

This template is intended for use in an article about a living person. For an article about a dead person, use {{tl|Birth date}} with {{tl|Death date and age}}.

{{notice|text='''Is the displayed age incorrect?'''<br>The age displayed was calculated when the page was last purged. If a particular article is showing the wrong age, edit the whole page and publish the edit without making any change and with no edit summary. That will update the age. The page can also be purged by appending <code>&action=purge</code> to the URL.}}

== Usage ==
; Unnamed parameters for year, month, day
: <code><nowiki>{{</nowiki>Birth date and age|''year of birth''|''month of birth''|''day of birth''|''additional parameters''<nowiki>}}</nowiki></code>
: <code><nowiki>{{</nowiki>bda|''year of birth''|''month of birth''|''day of birth''|''additional parameters''<nowiki>}}</nowiki></code>

; Named parameters for year, month, day
: <code><nowiki>{{</nowiki>Birth date and age|year=''year of birth''|month=''month of birth''|day=''day of birth''|''additional parameters''<nowiki>}}</nowiki></code>
: <code><nowiki>{{</nowiki>bda|year=''year of birth''|month=''month of birth''|day=''day of birth''|''additional parameters''<nowiki>}}</nowiki></code>

=== Additional parameters ===
The '''df''' (day first) and '''mf''' (month first) parameters indicate the intended date format to display. The appropriate parameter should be set to "y" or "yes" e.g. '''df=yes''' or '''mf=y'''.

The default output of this template is to display the month before the day. This default may not be appropriate for articles about people from parts of the world where the day precedes the month in a date. In such articles the parameter, "df", should be set to display the day before the month.

The parameter "mf", while not actually used by the template, will indicate that month first format is intended. Using these parameters can assist [[WP:BOT|bots]] or other automated processing to detect which date format is intended; leaving the format as default may lead an editor or bot to change the format to an unintended value.

Do not specify both "df" and "mf" parameters in the same use of the template, as these formats are mutually exclusive.

=== Error tracking ===
Some kinds of invalid input are tracked in [[:Category:Pages using age template with invalid date]].

=== Notes ===
* '''Do not use with non-Gregorian dates''' because the resulting hCard hidden date will be false.
* The template will appear broken when the parameters are left blank.
* When only the month or year of a person's birth and/or death are known, or if it is desired not to state a person's full dates of birth for privacy reasons, consider using the templates {{tl|Birth year}} or {{tl|Birth year and age}} instead.

== Examples ==
; Unnamed parameters for year, month, day
: <code><nowiki>{{Birth date and age|1993|2|24}}</nowiki></code> returns "{{Birth date and age|1993|2|24}}"
: <code><nowiki>{{Birth date and age|1993|2|24|df=yes}}</nowiki></code> returns "{{Birth date and age|1993|2|24|df=yes}}"
: <code><nowiki>{{Birth date and age|1993|2|24|mf=yes}}</nowiki></code> returns "{{Birth date and age|1993|2|24|mf=yes}}"

; Named parameters for year, month, day
: <code><nowiki>{{Birth date and age|year=1993|month=2|day=24}}</nowiki></code> returns "{{Birth date and age|year=1993|month=2|day=24}}"
: <code><nowiki>{{Birth date and age|year=1993|month=2|day=24|df=yes}}</nowiki></code> returns "{{Birth date and age|year=1993|month=2|day=24|df=yes}}"
: <code><nowiki>{{Birth date and age|year=1993|month=2|day=24|mf=yes}}</nowiki></code> returns "{{Birth date and age|year=1993|month=2|day=24|mf=yes}}"

=== Using full date in one parameter ===
The following examples use a parameter value that will not work in the {{tl|Birth date}}, {{tl|Death date}}, or {{tl|Death date and age}} templates.

The date format entered does not change the date format displayed, which is MDY by default or DMY if <code><nowiki>|df=y</nowiki></code> (to display the date in the same format it was entered, use {{tlp|Birth-date and age}}).

; Unnamed parameter for full date (output in MDY format)
: <code><nowiki>{{Birth date and age|1993-2-24}}</nowiki></code> returns "{{Birth date and age|1993-2-24}}"
: <code><nowiki>{{Birth date and age|Feb 24, 1993}}</nowiki></code> returns "{{Birth date and age|Feb 24, 1993}}"
: <code><nowiki>{{Birth date and age|24 Feb 1993}}</nowiki></code> returns "{{Birth date and age|24 Feb 1993}}"

; Unnamed parameter for full date (output in DMY format)
: <code><nowiki>{{Birth date and age|1993-2-24|df=y}}</nowiki></code> returns "{{Birth date and age|1993-2-24|df=y}}"
: <code><nowiki>{{Birth date and age|24 Feb 1993|df=y}}</nowiki></code> returns "{{Birth date and age|24 Feb 1993|df=y}}"
: <code><nowiki>{{Birth date and age|Feb 24, 1993|df=y}}</nowiki></code> returns "{{Birth date and age|Feb 24, 1993|df=y}}"