How are months counted?

By calendar, not by 30-day blocks. From January 31 to March 1 is 1 month 1 day, because February's real length is used.

Do leap years matter?

Yes — total-day counts are computed from real calendar dates, so February 29 is included whenever it occurs in the span.

Age & Date Span Calculator

Exact years, months, and days between dates.

From (e.g. birth date)ToDefaults to today

Span

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Pick both dates.

Two dates in, and the span comes back the way people actually say it — years, months, days — alongside the totals: days, weeks, hours, minutes. Calendar-accurate, so month lengths and leap years are respected rather than approximated.

How to use it

1.Pick the first date (a birthday, a start date).
2.Pick the second date, or leave it as today.
3.Read the span as years/months/days and as totals.

Questions people ask

How are months counted?: By calendar, not by 30-day blocks. From January 31 to March 1 is 1 month 1 day, because February's real length is used.
Do leap years matter?: Yes — total-day counts are computed from real calendar dates, so February 29 is included whenever it occurs in the span.

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