Short answer
A person born on 29 February has a calendar birthday only in leap years, about 1 in every 1,461 births. In other years the legal birthday is 28 February or 1 March depending on local law.
1. The leap year rule
A year is a leap year if it is divisible by 4, except century years not divisible by 400. So 2000 and 2024 are leap years, while 1900 and 2100 are not.
2. What happens in other years
- The legal birthday is 28 February or 1 March, depending on local law.
- Age in completed years still increases by one each year.
- The Age Calculator shows 1 March as the next birthday in a non-leap year.
3. Real birthdays
Someone born on 29 February 2000 had their sixth calendar birthday on 29 February 2024, when they turned 24.
4. Counting days
Total days lived are exact in any case because the calendar counts every real day. See how to calculate exact age.
5. Frequently asked questions
When is a leap-day birthday in a normal year?expand_more
Either 28 February or 1 March, depending on local law. This tool uses 1 March.
How old is someone born on 29 February 2000 in 2024?expand_more
They are 24 and had their sixth calendar birthday on 29 February 2024.
Is 2100 a leap year?expand_more
No. Century years are leap years only if divisible by 400.
Does a leap-day baby age more slowly?expand_more
No. They gain one year of age each year, only the calendar date differs.