Leap Year Checker

Instantly verify if a year is a leap year

Result

Leap Year Rules

Divisible by 4: A year is a leap year if it's divisible by 4

Exception for centuries: If the year is divisible by 100, it's NOT a leap year unless...

Divisible by 400: The year is a leap year if it's also divisible by 400

Recent Checks

Leap Year Checker Tool

Our free leap year checker instantly determines whether any given year is a leap year according to the Gregorian calendar rules. Whether you're programming, planning events, or just curious about calendar calculations, our tool provides quick and accurate results.

How to Use the Leap Year Checker

Enter a year in the input field (any year from 1 to 9999)
Click the "Check" button or press Enter
View the result showing whether the year is a leap year
Review the leap year rules below the result
See your recent checks in the history section

Understanding Leap Years

A leap year is a year containing one additional day (February 29) to keep the calendar year synchronized with the astronomical year. The Gregorian calendar uses these rules to determine leap years:

Year	Divisible by 4	Divisible by 100	Divisible by 400	Leap Year?
2020				Yes
1900				No
2000				Yes
2023				No

Why Do We Have Leap Years?

Leap years exist because a single revolution of the Earth around the Sun takes approximately 365.2422 days (a tropical year). Without leap years, our calendar would gradually drift out of alignment with the Earth's revolutions around the Sun. By adding an extra day every four years (with exceptions), we keep the calendar year synchronized with the astronomical year.

Common Uses for Leap Year Checking

Programming

Date calculations in software development

Event Planning

Scheduling recurring annual events

Education

Teaching calendar systems and astronomy

Frequently Asked Questions

While 1900 is divisible by 4, it's also divisible by 100 but not by 400. According to leap year rules, century years must be divisible by 400 to be leap years. This correction accounts for the slight discrepancy in the length of a tropical year.

Leap years typically occur every 4 years, but century years (divisible by 100) are exceptions unless they're also divisible by 400. This means the pattern is: 3 normal years, then 1 leap year, repeating until a century year, which may or may not be a leap year.

The next leap years after 2023 are 2024, 2028, 2032, and so on every 4 years. The next century leap year (divisible by 400) will be 2400.