About this tool
Enter a date of birth to see an exact age in years, months and days, along with the total months, weeks and days lived, the weekday you were born on and a countdown to the next birthday. Change the second date to work out how old someone was — or will be — on any day.
How to use it
- Pick the date of birth.
- Leave the second date as today, or choose any other date.
- Read the exact age and the extra details below it.
Good to know
- Months are counted calendar-accurately, so 31 January to 29 February is exactly one month.
- People born on 29 February have their birthday counted on 28 February in non-leap years.
- Dates are calculated on the calendar only, so time zones never change the result.
Frequently asked questions
How is age calculated?
Whole years and months are counted from the birth date, then the remaining days. This matches how ages are written on official forms.
Can I calculate age on a past or future date?
Yes. Change the second date to any day after the date of birth to see the age on that day.