A leap year is a year containing one additional day (February 29th), making it 366 days long. This keeps our calendar in alignment with the Earth's revolutions around the Sun.

How do you calculate a leap year?

A year is a leap year if it is divisible by 4. However, if it is divisible by 100, it is NOT a leap year, unless it is also divisible by 400. For example, 2000 was a leap year, but 1900 was not.

Why do we need leap years?

It takes Earth approximately 365.24 days to orbit the Sun. Without leap years, we would lose about 6 hours every year, and after 100 years, our calendar would be off by about 24 days!

Is every 4th year a leap year?

Almost, but not exactly. The "divisible by 100 but not 400" rule is the exception. This adjustment makes the average calendar year 365.2425 days long, which is very close to the actual solar year.

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Leap Year Checker

Check if a year is a leap year

How to Use

Enter the year you want to check (e.g., 2024, 2025, 2100)
Click the "Check" button
See if the year is a leap year (366 days) or not (365 days)
View how many days February has in that year
Fun fact: Leap years include 2020, 2024, 2028, but not 1900 or 2100
Rule: Leap if divisible by 4, except centuries unless divisible by 400

About This Tool

Instantly determine whether any year is a leap year with our leap year checker. Leap years occur every four years (with some exceptions) to keep our calendar synchronized with Earth's orbit around the sun. These years have 366 days instead of the usual 365, with February getting an extra day (29th). This tool is perfect for calendar planning, understanding date calculations, historical research, birthday tracking for leap day babies, or simply satisfying curiosity. The checker uses the official leap year rules: divisible by 4 but not by 100, unless also divisible by 400. Know instantly if any year has 365 or 366 days.

what is Leap Year Checker

Curious if a specific year has 366 days instead of 365? Our Leap Year Checker instantly determines if any given year is a leap year. Simply enter the year (e.g., 2024, 2000, 1900), and the tool will tell you the result along with a brief explanation of why it is or isn't a leap year. This is useful for historical research, programming logic, or just settling a debate.

Key Benefits:

Instantly check any year from the past or future
Clear "Yes" or "No" results
Explains the logic behind the result
Works for Gregorian calendar years
Fast and lightweight tool

Frequently Asked Questions

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