Age Calculator
Calculate exact age in years, months, and days, plus the next birthday.
Result
Select a date of birth.
How exact age is calculated
Exact age advances through calendar anniversaries, then counts complete months and days up to the target date. This respects actual month lengths rather than assuming every month has 30 days.
Years, months, and days
Years are completed birthdays. Additional months and days describe the time since the latest birthday. Total days come from calendar dates; total months are approximate completed months because months have unequal lengths.
Next birthday
The calculator finds the next anniversary after the target date and counts the calendar days remaining.
February 29 birthdays
In non-leap years, this calculator uses February 28 as the anniversary. In a leap year it returns to February 29. This calculation convention may differ from local legal rules.
Frequently asked questions
Why not divide total days by 365?
Leap years and unequal month lengths make that shortcut unsuitable for an exact calendar age.
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