Age Calculator
Pick a date of birth and, if you need an age on a past or future date, change the second date. The result is the calendar age plus the totals people usually ask for next.
Pick a date of birth.
About this tool
Age is a calendar difference, not a division: the tool counts whole years, then whole months, then borrows days from the previous month exactly the way you would on paper. That handles leap years and short months without any fudge factor.
The same calculation answers a lot of everyday questions — eligibility for a licence or pension, a child's age in months for growth charts, or how long ago something happened in days.
Frequently asked questions
- How is age calculated exactly?
- By counting complete years since birth, then complete months, then the remaining days — borrowing from the previous month when the day of the month has not yet been reached.
- How do leap years affect the result?
- They do not distort the calendar age, because the calculation works in calendar units. They only shift the total-days figure by one day per leap year passed.
- Can I calculate an age on a future date?
- Yes. Change the second date to any date after the birth date and the result updates.
- Why does the month count sometimes look off by one?
- A month is only counted once the day of the month has been reached. Born on the 30th and asked on the 29th, that month is not yet complete.