Leap Year Calculator

Check leap years, calculate days between dates, and explore date arithmetic

Check Any Year

Enter Year

Days Between Dates

Start Date

End Date

Calculate business days (Mon-Fri)

Leap Years in Range

Start Year

End Year

Found 25 leap years:

2000200420082012201620202024202820322036204020442048205220562060206420682072207620802084208820922096

Leap Year Rules

The Gregorian Calendar Rules

A year is a leap year if it is divisible by 4
EXCEPT if it is divisible by 100, then it is NOT a leap year
UNLESS it is also divisible by 400, then it IS a leap year

Examples of Leap Years

✅ 2024 (divisible by 4)
✅ 2000 (divisible by 400)
✅ 1600 (divisible by 400)
✅ 2028 (divisible by 4)

Examples of Non-Leap Years

❌ 2023 (not divisible by 4)
❌ 1900 (divisible by 100, not 400)
❌ 2100 (divisible by 100, not 400)
❌ 2025 (not divisible by 4)

Why Do We Have Leap Years?

The Earth takes approximately 365.2422 days to orbit the Sun. To keep our calendar aligned with the seasons, we add an extra day every 4 years. The century exceptions (100 and 400 rules) fine-tune this to get even closer to the actual orbital period.