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Age calculator

Enter your date of birth — the exact calendar age, your birth weekday and the next-birthday countdown update instantly.

Calculator

Exact age
Next birthday
Born on a

How it works

Calendar age subtracts year, month and day separately: the day deficit borrows one month from the month before today, and a negative month count borrows one year. February 29 birthdays fall on March 1 in common years. No approximations — the result is exact calendar arithmetic.

Frequently asked questions

Is the age exact or approximate?
Exact. The calculator performs real calendar subtraction — including unequal month lengths and leap years — not 365.25-day averaging.
Why do some months show 30 or 31 days when borrowing?
When your day-of-month is smaller than today's, the calculator borrows the actual length of the previous month, so the days figure matches how calendars really work.
How is a February 29 birthday handled?
The next birthday lands on March 1 in common years and February 29 in leap years, matching the usual convention for leap-day births.

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Date differenceCountdownDay of week