Age Calculator
Work out an exact age from a date of birth: years, months and days, the same in weeks and days, the weekday of birth, and how long until the next birthday.
Runs in your browser. Nothing you enter is uploaded.
How to use
This calculator works out an exact age from a date of birth, counted the way a calendar counts it.
- Choose the Date of birth.
- Age on starts at today. Choose another date to see the age on that day instead, such as the start of a school year, a deadline or a date in the past. Today goes back to today.
- Read the age in years, months and days, and underneath it the same age in months, in weeks and in days, the day of the week the person was born on, and when the next birthday is, how many days away, and the age it brings.
Ages are counted in whole calendar months, starting from the birth date each time. Someone born on the 31st has a month's birthday on the last day of shorter months, so from 31 January to 28 February is one month. Someone born on 29 February has their birthday on 28 February in years without one.
The dates are your device's calendar dates, without times, so the answer doesn't change with time zones or summer time. Nothing you type is stored or sent anywhere: the date of birth stays on this page and is gone when you leave it.
For the number of days, weeks or working days between any two dates, use the date calculator.
Frequently asked questions
How is age calculated?
In whole years since the date of birth, then whole months since the last birthday, then the days left over. On a birthday the age goes up by one year.
When does someone born on 29 February have a birthday?
Here, on 28 February in years without a 29 February. Some countries' laws count 1 March instead, so for legal purposes check the rule where you are.
Is the date of birth saved?
No. It stays in this page while you use it and isn't stored on your device or sent anywhere.
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