How to Calculate Your Exact Age in Years, Months and Days
Working out an exact age is trickier than it looks because months and leap years vary. Learn the simple way to calculate age precisely with a free calculator.
Calculating someone age in whole years is easy, but working out the exact years, months and days is surprisingly fiddly because months have different lengths and leap years add an extra day. Here is how to get it right.
Why exact age is tricky
To find an exact age you subtract the birth date from today date, borrowing across months and years when the day or month has not yet been reached. Because February and leap years vary, doing this by hand is error-prone.
The simple method
- Take the difference in years between the two dates.
- If the current month/day is before the birth month/day, subtract one year.
- Work out the leftover months and days.
Or skip the arithmetic entirely.
Calculate age instantly
Enter a date of birth into the free Age Calculator to see the exact age in years, months, days and total days. It is useful for forms, birthdays and eligibility checks.
If you work with timestamps in code or spreadsheets, the Unix Timestamp Converter turns timestamps into readable dates and back.