Leap Year Calculator
Free, locally-processed leap year calculator for fast and secure results.
Runs locally in your browser
Your inputs are processed locally in your browser and are not uploaded or stored by us.
Check whether a specific calendar year is a leap year and understand the Gregorian leap year rules.
How to use the Leap Year Calculator
- Enter a 4-digit calendar year.
- Select Calculate.
Calculation methodology
Leap Year = (Divisible by 4 AND NOT Divisible by 100) OR Divisible by 400
The calculator applies the strict Gregorian mathematical rules to determine if February has 28 or 29 days.
Worked example
Year2000
2000 is divisible by 4. It is a century year (divisible by 100), but it is also divisible by 400. Therefore, it is a leap year.
Result: Is a leap year (366 days)
Notes
- Was 1900 a leap year? No. It is divisible by 4 and 100, but not by 400.
- Was 2024 a leap year? Yes.