Calculate your exact age in years, months, days and find your next birthday
An age calculator works out exactly how old someone is from their date of birth — not just the year count, but the precise years, months and days, and often the total in hours or days too. Counting age by hand is deceptively tricky because months have different lengths and leap years add a day every four years, so "how many days until my next birthday?" or "how old will I be on this date?" are easy to get slightly wrong. This tool does the calendar arithmetic correctly so the answer is exact.
Beyond curiosity, an exact age matters for real tasks: eligibility cutoffs, forms that ask for age in years and months, working out the gap between two dates, or counting down to a milestone birthday. Because it computes against the actual calendar, it accounts for the varying month lengths and leap days that simple subtraction ignores. Everything runs in your browser, so the date you enter is never sent anywhere.
Yes. The calculation works against the real calendar, so leap days (29 February) and the differing lengths of months are handled correctly. This is why an exact age tool differs from simply subtracting years.
Because leap years add an extra day roughly every four years, so a lifetime accumulates more days than years × 365. The day count includes those extra leap days, which makes it slightly higher than a naive estimate.
In non-leap years there is no 29 February, so the birthday is conventionally observed on 28 February or 1 March depending on the rule used. The calculator counts whole years consistently, giving a sensible age either way.
Yes. The same calendar arithmetic works for any pair of dates, so you can measure service length, a subscription period or the gap between two events, not only age from a birth date.
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