How do I calculate age from a birthday?

Enter birth date for age in years, months, and days.

Does it account for leap years?

Yes. Uses standard calendar date math.

Age and days between dates.

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Date 1

Date 2

Calculate exact age in years, months, and days from a birthday, or count days between two dates for deadlines.

How do I calculate age from a birthday?: Enter birth date for age in years, months, and days.
Does it account for leap years?: Yes. Uses standard calendar date math.

Last updated: 2026-05-31