Age Calculator
Compute years, months, and days from a birth date to today (or an optional end date).
Inputs
Age
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Frequently asked questions
- How is age calculated?
- Age is the difference between the birth date and the “as of” date, broken into years, months, and days.
- Which date should I use as “today”?
- Use the as-of date field. Leave it as today for current age, or set a past/future date for a snapshot.
- Does it handle leap years?
- Yes—calendar month/day boundaries follow the Gregorian calendar, including Feb 29 edge cases.
- Is the result exact to the hour?
- No. This calculator works in whole calendar days, not hours or time zones.
- What if birth date is after the as-of date?
- Birth must be on or before the as-of date. Swap the dates or correct the year if the result is rejected.
- How is this different from days-between-dates?
- Days-between returns a single day count. Age expands that span into years + months + remaining days.