How it works
This age calculator finds the exact difference between your date of birth and a comparison date (today, by default) — down to the year, month, and day. It borrows from the previous month when the day count goes negative, so results stay accurate across different month lengths and leap years, which JavaScript's date math handles automatically. Alongside your exact age, it shows the total number of days and weeks you've been alive and counts down the days until your next birthday. Enter any two dates to check someone else's age or plan around a milestone birthday.
Age Calculator
Find your exact age in years, months, and days.
FAQ
How does the calculator handle leap years?
JavaScript's date arithmetic naturally accounts for leap years when computing the difference between two dates, so no special handling is needed for most cases.
What happens with a February 29 birthday in a non-leap year?
This calculator treats a Feb 29 birthday as observed on Feb 28 when counting down to the next birthday in a non-leap year, rather than letting it overflow into March 1.
Can I calculate someone else's age, or age at a past/future date?
Yes — enter any date of birth and any comparison date; it doesn't have to be today, so you can check age at a specific past event or a future milestone.
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