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Age calculator

Nothing you type leaves this device.

Counted the way a registrar counts: whole years, then whole months, then the days left over.

Enter a date of birth and the age appears here, counted against your own clock.

The short answer

Age counts whole years first, then whole months, then the days left over. That is the order a registrar uses. It is also why this answer can sit a day or two away from tools that take the total days and divide by 30.44.

Counted against your own clock. No date you enter is sent anywhere, which matters more than it sounds when the date is a child’s.

The formula

whole years, then whole months from the anniversary, then the remaining days

Worked examples

born 14 Mar 1990, on 1 Jan 2026
35 years, 9 months, 18 days
born 29 Feb 2000, on 28 Feb 2026
26 years, 0 months, 0 days
born 31 Jan 2026, on 28 Feb 2026
0 years, 1 months, 0 days

Reference table

The awkward cases, worked through
BornOnAge
31 Jan 202628 Feb 20260 years, 1 months, 0 days
31 Jan 20261 Mar 20260 years, 1 months, 1 days
29 Feb 200028 Feb 202626 years, 0 months, 0 days
29 Feb 20001 Mar 202626 years, 0 months, 1 days

How to use it

  1. 01Enter the date of birthUse the date field. It opens your device's own picker, and the date never leaves the page.
  2. 02Read the four figuresYears, months and days over, total days lived, and days until the next birthday. Years is pinned at the bottom because it is the one people came for.

Also searched for

Searches that land here include age calculator, how old am I, age in days, days until my birthday and date of birth calculator.

About counting ages

Why two calculators disagree by a day

Months are not equal lengths, so "one month and three days" depends on which month you count from. This counts forward from the birth date, borrowing from the previous calendar month when the day of month has not yet come round — the same convention a registrar uses. Tools that convert to days first and divide by 30.44 will differ by a day or two, and neither is wrong so much as differently defined.

Questions people ask

Does it account for leap years?

Yes. The day count is a true difference between two dates, so every 29 February you have lived through is included.