To calculate exact age, enter a date of birth and, optionally, the date to measure to; the Age Calculator returns the age in years, months and days. It defaults to today.
How to use the Age Calculator
- Enter the date of birth.
- Optionally change the as-of date.
- Read the age in years, months and days.
- Copy the result.
Worked example
Someone born on 15 March 2000 is 25 years, 6 months and 4 days old on 19 September 2025.
Tips and common mistakes
- Change the as-of date to find age at a past or future event.
- Leap-year birthdays are handled by calendar rules.
- Months and days are counted from the last birthday.
Frequently asked questions
Can I calculate age on a future date?
Yes, set the as-of date.
Does it handle leap years?
Yes.
Is my date stored?
No. It stays in your browser.