Leap Year Calculator
Check if a year is a leap year, see its number of days, and find the next leap year. Uses the full Gregorian rule, including the 100 and 400 year exceptions.
Independently verified for accuracy
Calculator by Toolsloft ↗- Leap year?
- No
- Days in year
- 365
- Next leap year
- 2028
Check whether any year is a leap year and see how many days it has. Enter a year and the tool tells you if it has the extra February 29, and which year the next leap year falls on. It follows the Gregorian calendar rules, including the century exceptions people often forget.
How this is calculated
A year is a leap year when it is divisible by 4, except that years divisible by 100 are not, unless they are also divisible by 400. This is the standard Gregorian calendar rule, which is why 2000 was a leap year but 1900 was not. Leap years have 366 days; all other years have 365.
How to use
- Enter the year you want to check.
- See whether it is a leap year and how many days it has.
- Read the next leap year shown below the result.
Examples
- A leap year:
2024 → yes, 366 days - A century exception:
1900 → no (divisible by 100, not by 400)
FAQ
- Why was 1900 not a leap year but 2000 was?
- Years divisible by 100 are not leap years unless they are also divisible by 400. 1900 is divisible by 100 but not 400, so it was a common year, while 2000 is divisible by 400 and so was a leap year.
- What is the simple version of the rule?
- Most years divisible by 4 are leap years. The only exception is the turn of a century: those years must be divisible by 400 to count. This keeps the calendar aligned with the solar year over time.
- How many days does a leap year have?
- A leap year has 366 days, with an extra day added as February 29. A common, non-leap year has 365 days.