Age Calculator

Runs in your browser — your data is never uploaded.

Work out an exact age — in years, months and days, plus total days — as of any date, not just today. Updates instantly as you change either date.

How to use Age Calculator

  1. 1

    Enter the birth date.

  2. 2

    Enter the date to calculate the age as of (defaults to today).

  3. 3

    The result updates automatically.

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Frequently asked questions

How are months and days worked out when the day-of-month differs?+

It counts whole years first, then whole months, then the leftover days — borrowing from the previous month where needed, the same way you’d work out an age by hand. That keeps the result consistent with how people naturally state an age.

Can I use it to count down to a birthday?+

Indirectly — set the birth date and a future “as of” date to see the exact age on that day. For a plain day count between now and any date, the date difference calculator is the more direct tool.

Can I calculate age as of a future or past date, not just today?+

Yes — the "as of" date defaults to today but can be set to any date, useful for calculating age at a specific event.

Is my data uploaded anywhere?+

No. The calculation runs entirely in your browser — nothing is sent to a server.