Age Calculator
Enter a birth date to get the exact age in years, months, and days — plus total months, total days, and the date and weekday of the next birthday. The "age on" date defaults to today and can be set to any date, past or future.
Calculate an age
Example: born 1990-06-15, on 2026-07-17 the age is 36 years, 1 month, 2 days.
How exact ages are counted
Age is anniversary arithmetic: whole years first, then whole months, then leftover days — each measured on the real calendar, so a month is "the same day next month", however long that month is. The example above also shows the totals: 433 months, or 13,181 days lived. Every figure on this page is computed by the same tested engine as the calculator itself.
Common uses
Filling in official forms that ask for age in years and months, checking eligibility cutoffs for school entry, sports categories, or benefits, computing an age at the date of an event or document, and — more cheerfully — birthday countdowns: the example person's next birthday falls on a Tuesday.
Frequently asked questions
How is the years-months-days age computed?
By counting whole calendar months from the birth date, then the remaining days — the way anniversaries work. Someone born June 15, 1990 is 36 years, 1 month, 2 days old on July 17, 2026, even though months differ in length.
What about people born on February 29?
In non-leap years the next birthday is taken as February 28, the most common civil convention. In leap years it falls on the true February 29.
Can I calculate age at a past or future date?
Yes — the "age on" field defaults to today but accepts any date, so you can compute someone’s age on a document date, an event date, or a future milestone.
Why does the total days figure matter?
Legal and administrative thresholds are sometimes defined in days (visa stays, insurance windows, eligibility cutoffs). The exact total avoids the rounding built into month-based ages.
Birth dates are processed locally in your browser and never transmitted or stored. See the methodology page.