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Leap Year Calculator
About the Leap Year Calculator
Check whether any year is a leap year, meaning it has 366 days with an extra 29 February.
How to use the Leap Year Calculator
- Enter the Year.
- Press Check year to see the answer and the reason.
Formula and method
A year is a leap year if it is divisible by 4, except century years, which must also be divisible by 400.
| Year | Leap year? | Reason |
|---|---|---|
| 2024 | Yes | Divisible by 4 |
| 2023 | No | Not divisible by 4 |
| 1900 | No | Century year not divisible by 400 |
| 2000 | Yes | Divisible by 400 |
| 2100 | No | Century year not divisible by 400 |
Worked example
2028 ÷ 4 = 507 with no remainder and 2028 is not a century, so it is a leap year.
Century years. 2024 is a leap year. 1900 was not, because it is divisible by 100 but not by 400. 2000 was a leap year, because it is divisible by 400.
When to use the Leap Year Calculator
- Checking whether a year has 366 days.
- Working out the correct number of days in February.
- Planning contracts and birthdays that fall on 29 February.
Common mistakes to avoid
- Thinking that every year divisible by 4 is a leap year. Century years are an exception.
Tips
- Leap years keep the calendar aligned with the Earth's orbit, which takes about 365.2422 days.
Frequently Asked Questions
Leap years occur every four years, for example 2028, 2032 and 2036.
A solar year is about 365.2422 days. The extra day every four years keeps the calendar in line with the seasons.
Enter a year in the tool to check, or look for years divisible by 4, such as 2028.