About Leap Year Checker
Free online leap year checker. Verify whether any year from 1 to 9999 AD is a leap year. Explains the 4-year, 100-year, and 400-year Gregorian rules with next and previous leap year dates.
Key Capabilities & Features
- Instant leap year verification
- Detailed Gregorian rule breakdown (divisible by 4, 100, 400)
- Days in year (365 vs 366)
- Days in February (28 vs 29)
- Next and previous leap year finder
How to Use Leap Year Checker
1
Enter Year
Type in any calendar year or click a preset.
2
Inspect Verdict
Read whether the year is a leap year or common year.
3
Review Rules
Understand the mathematical rule applied.
Privacy & In-Browser Execution Guarantee
100% in-browser calculation. No server requests.
Frequently Asked Questions
Why are century years not always leap years?
Century years like 1900 and 2100 are divisible by 100 but not by 400, so they are common years of 365 days.
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