Age Calculator
Find your exact age in years, months and days from your date of birth, on today’s date or any other date.
These health tools are still being tested and are updated regularly to give you a better experience. Results are estimates for information only — please confirm important results with a doctor. Read the medical disclaimer
Age Calculator
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About the Age Calculator
Exact age is needed for forms, medicine doses for children, vaccination schedules and eligibility checks.
How to use the Age Calculator
- Enter the date of birth.
- Keep today as the “age on” date or choose another date.
- Press Calculate to see the exact age, totals and the next birthday.
Formula explained
Age = chosen date − date of birth
Years are counted first, then whole months, then the remaining days, taking month lengths and leap years into account. Total days = the difference between the two dates.
Worked example: Age
Born on 21 March 1988, on 7 November 2026 a person is 38 years, 7 months and 17 days old — 14,110 days in total. The next birthday is 21 March 2027, in 134 days.
Important limitations
- Uses the Gregorian calendar and your device’s date.
- Does not account for the time of day of birth.
Frequently asked questions
How are leap years handled?
The calculator uses the real calendar, so 29 February and month lengths are counted correctly.
Can I calculate age on a past or future date?
Yes. Change the “age on” date to any date you need.
How is age counted for medical forms?
Most forms use completed years (your age at your last birthday). For babies and young children, doctors often use completed months or weeks, which this calculator also shows.
Why is my age in days not exactly years × 365?
Because of leap years — every fourth year has 366 days — and because months have different lengths.
Sources
- Gregorian calendar date arithmetic.
Medical disclaimer: These tools give general information and estimates only. They are not a diagnosis and do not replace advice from a qualified doctor. Always talk to your doctor about your results, and seek urgent medical help in an emergency. In an emergency call 112. Medical disclaimer · Terms of use · Privacy policy
