Leap Year Calculator
Check whether a year is a leap year under the Gregorian calendar rule, see whether February 29 exists, and list leap years in a selected range.
Check whether a year is a leap year
This calculator follows the Gregorian calendar rule used by the modern civil calendar: most years divisible by 4 are leap years, except century years unless they are divisible by 400.
For example, 2024 is a leap year, 1900 and 2100 are common years, and 2000 is a leap year.
What the result includes
- Leap-year or common-year verdict.
- 365-day or 366-day year length.
- Whether February 29 exists in the selected year.
- Previous and next leap years.
- Leap years in a custom range.
Frequently Asked Questions
Sources and References
- DateMDN Web Docs
- Representing dates and timesMDN Web Docs
- Gregorian calendarBritannica
- ISO 8601 date and time formatISO
- International System of Units: TimeNIST
Calculations are based on the listed reference sources. Links open in a new tab.
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