Age Calculator
Calculate exact age in years, months and days from a date of birth — plus total days lived, the next birthday and the day you were born.
How to use
- 1Enter the date of birth.
- 2Optionally change the 'age on' date to find someone's age on a past or future day.
How it's calculated
Whole years and months are counted on the calendar; leftover days are counted from the same day of the previous month. People born on 29 February turn a year older on 28 February in common years.
Frequently asked questions
How is age calculated exactly?
We count complete calendar years, then complete months, then remaining days — the way ages are normally stated, rather than dividing days by 365.
When does someone born on 29 February have a birthday?
In common years we show 28 February, which many countries use legally. Some use 1 March instead.
Can I calculate age on a future date?
Yes. Set 'Age on' to any date, for example to check eligibility or retirement age.