How your age is calculated
Your age is the time elapsed between your birth date and the chosen date. Because months have different lengths and leap years add a day, the calculator uses the real calendar rather than a fixed "30-day month", so the result is exact.
Common uses
- Checking eligibility based on a specific date (school, work, retirement).
- Counting down to a birthday or anniversary.
- Finding the age gap between two people or events.
Frequently asked questions
How does the age calculator work?
It finds the difference between your date of birth and a chosen date (today by default), accounting for the varying lengths of months and for leap years, then expresses it as years, months and days.
How is age counted with leap years?
The calculator uses the actual calendar, so the extra day in a leap year (29 February) is included automatically in the day and total-day counts.
Can I calculate age on a future or past date?
Yes. Change the second date to any date on or after your birth date to find how old you were, or will be, on that day.