This template employs intricate features of template syntax.
You are encouraged to familiarise yourself with its setup and parser functions before editing the template. If your edit causes unexpected problems, please undo it quickly, as this template may appear on a large number of pages.
Remember that you can conduct experiments, and should test all improvements, in either the general Template sandbox or your user space before changing anything here.
Start-date (birth-date) and end-date (death-date) are easy to read "plain text" date and time templates that emit microformat dates for events. These templates are an alternative to the {{start date}}/{{birth date}} and {{end date}}/{{death date}} templates that also emit microformats but require dates to be expressed in standard, unambiguous and international ISO syntax. "Fuzzy" dates and times are supported. For events where the precise time, day or month is not known, the user may omit these details. Time zones are assumed to be local to the event. If time zone information is specified, the otherwise optional timezone parameter must be set.
Usage examples
Start-date & End-date usage (colors for emphasis only):
Sample below displays Did not recognize date. Try slightly modifying the date in the first parameter., and microformat date: 1941-12-07
{{start-date|7 December 1941}}
Sample below demonstrating how days, timezones and hours, minutes and seconds can be shown. (Order often not important). Displays Did not recognize date. Try slightly modifying the date in the first parameter., and microformat date (corrected for UTC): 1941-12-08T03:43Z
{{start-date|5:43PM HST, December 7th, 1941|tz=y}}
Sample below demonstrates providing a location with local time to generate UTC value. Displays Did not recognize date. Try slightly modifying the date in the first parameter., and microformat date (corrected for UTC): 1941-12-08 T03:20Z
{{start-date| December 8, 1941 12:50PM Australia/Adelaide|tz=y}}
Sample below demonstrating use of Julian calendar dates. Displays Did not recognize date. Try slightly modifying the date in the first parameter., and microformat date: 1672-06-09
{{start-date|9 June 1672|{{OldStyleDate|9 June|1672|30 May}} }}
Parameters
parameter 1 (required) The date and time to display and to emit as a microformat date. If year is absent, the current year is assumed. If day is missing, the first of the month is assumed. If hour, or minutes are missing, zero is assumed. If time zone or location is missing, the local time of the event discussed in the article is assumed. See timezone parameter if UTC time is desired. Authors may specify place names (see list) or time zones such as EDT, PST, HST and so on and these will be properly adjusted to UTC (Coordinated Universal Time) for transfer to other applications via microformat encoding. Gregorian calendar dates are required. Display in Julian or Chinese calendar date is possible using parameter 2.
ISO8601 (optional) if present, this ISO8601 date/time value is emitted instead of the value derived from parameter 1.
BCE (required for BCE dates) set to yes if the date is BC.
timezone (required if timezone information specified) Set to yes if the time is UTC or if the location, timezone, or timezone offset is specified. (short form tz)
Ambiguous times and dates
For the years 99 BC to 99AD especially, microformats may not be emitted properly unless expressed in the form YYYY-MM-DD. For users uninterested in microformats, it should be noted that this restriction has no known impacts other than microformat data which are currently invisible to users. The user of course may express the display form in the second parameter however they would like. Example: 1-2-3 is interpreted as February 3, 1 A.D, and emitted in that form via microformats when the user may have intended something else. Other 3 digit years may be misinterpreted as well, so best practice is to use leading zeros to make a 4 digit year for this date range. For example, February 274 will be interpreted as February 27, 2004. Instead, use "February 0274". Background: There is a good rationale for the behavior of the system function which actually does the hard work of this template. It is very unusual for people to mention such dates so long ago, so when we really mean this date, we must specify a 4 digit date. Outside of this period with ambiguous years, users may use free text dates without this restriction. Bot runs may make a conversion of non 4 digit years to 4 digits (with leading zeros) in order to refine Wikipedia's quality of microformat dates. These changes will not affect display, but for those curious, this is the rationale for such bot manipulations.
