Age calculator
Calculate your exact age in years, months and days — or anyone’s age between a birth date and any date you choose.
Required fields are marked with an asterisk (*).
The age calculator uses the Gregorian calendar to compute your age precisely in years, months and days, between a birth date and any date you choose (today by default). The calendar-based math handles leap years and differing month lengths automatically.
Formula
Age = the calendar difference between the birth date and the calculation date, split into years, months and days.
When is this useful?
Use it for your exact age on official forms, to see how many days to your next birthday, or the age between any two dates.
Worked example
Example using the calculator’s values: born 2000-01-01 as of 2024-01-01.
Age 24 years, i.e. 288 months, 8,766 days, or 1,252 weeks.
Days until next birthday: 0.
Assumptions
- The calculation is Gregorian only (not Hijri).
- Age is computed on the given date without counting time of day.
- The calculation date is inclusive: it includes the day of the age itself.
- Leap-day births (29 February) are handled using 28 February or 1 March depending on the year.
Common mistakes
- Mixing Hijri and Gregorian dates — this calculator is Gregorian only.
- Entering the birth date as the calculation date, which yields age zero.
- Assuming age is measured by time (hours and minutes) rather than by date.
Frequently asked questions
How does the calculator handle 29 February births?
In non-leap years the birthday is counted on 28 February or 1 March per the calendar, and age is handled on a calendar basis rather than actual days.
Is the calculator Hijri or Gregorian?
Gregorian only. To compute a Hijri age you first need to convert the Hijri date to Gregorian.
Methodology and review
Results are in the Gregorian calendar and may differ from a Hijri age or official calculations using other standards.