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 organisations, 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.