Age calculator
This age calculator finds exact age in years, months and days from a date of birth to any other date. It also counts total days lived and shows when the next birthday falls. People use it for forms, school and sports age limits, and birthday planning.
- Runs in your browser
- Free, no account needed
- Copy or download the result
Result
Example
Date of birth: 1990-05-15 Age as of: 2026-10-30 Birthdays on a day a month does not have: Use the last day of the month (Feb 29 to Feb 28)
Age: 36 years, 5 months, 15 days Total: 13,317 days (1,902 weeks and 3 days), or 437 full months Next birthday: Saturday, May 15, 2027, turning 37, in 197 days Born on: Tuesday, May 15, 1990 As of Friday, October 30, 2026. The birth date itself is not counted in the day total. Months are counted from the birth day of the month to the same day of a later month.
How to use the age calculator
- Pick your Date of birth.
- Set Age as of to today or any other date. It starts at 2026-10-30 as an example.
- If the birthday is on the 29th, 30th or 31st, choose how to handle months that lack that day.
- Press Run, then use Copy result or Download.
How it works
Age is the number of whole months from the birth date to the "as of" date, split into years and months, plus the days left over.
Total days count every day after the birth date up to and including the "as of" date.
For a February 29 birthday in a common year, the default rule uses February 28. You can switch to March 1 instead. The same rule applies to any birthday on the 29th, 30th or 31st in a month too short to have that day, so it can change the months and days for those birthdays.
Dates use the Gregorian calendar for years 0001 to 9999, and the birth date must not be after the "as of" date.
Everything runs in your browser. Your input is not uploaded or stored.
Questions and answers
How is exact age calculated?
The calculator counts whole months from your birth date to the chosen date, turns every 12 months into a year, and counts the days left over. For example, May 15, 1990 to October 30, 2026 is 36 years, 5 months and 15 days.
When does someone born on February 29 turn a year older?
In leap years it is February 29. In common years the law and custom vary, so this tool lets you choose February 28 (the default) or March 1.
Can I find my age on a future or past date?
Yes. Change Age as of to any date on or after the date of birth, such as an exam date or a retirement date.
Is my birth date sent anywhere?
No. The calculation runs in your browser and nothing is stored.