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Leap Year Checker

Just enter a year to instantly find out whether it is a leap year or a common year. See the number of days in the year (366 or 365), the days in February (29 or 28), and the nearest leap years before and after.

Input

Result

Enter the year you want to check.

How it works

  • The basic rule is that any year divisible by 4 is a leap year. For example, 2024 and 2028 are leap years because they are divisible by 4.
  • There is an exception, though: years divisible by 100 revert to common years. 1900 and 2100 are divisible by 4, but because they are also divisible by 100 they are not leap years.
  • As an exception to that exception, years divisible by 400 are leap years. 2000 and 2400 are divisible by 100, but because they are also divisible by 400 they are leap years.
  • A leap year has 366 days, with February running through the 29th. A common year has 365 days, with February ending on the 28th. Leap years occur roughly once every four years.
  • Enter a year and this tool reports the leap or common year verdict along with the number of days in that year, the days in February, and the nearest leap years before and after.
  • Leap years exist to correct the gap between the time it takes Earth to orbit the Sun (about 365.2422 days) and the 365-day calendar year.