About this tool
Find out instantly whether any year is a leap year, with the reasoning, computed in your browser.
Frequently asked questions
What makes a year a leap year?
A year is a leap year if it is divisible by 4, except century years, which must also be divisible by 400.
Why is 1900 not a leap year but 2000 is?
1900 is divisible by 100 but not 400, so it is skipped, while 2000 is divisible by 400 and counts.