Leap Year Checker Calculator
Find out if a year is a leap year instantly
Result
The year 2024 is a leap year.
Explanation
The year 2024 is divisible by 4 and not divisible by 100, or it is divisible by 400, which makes it a leap year.
About This Leap Year Calculator
Understanding how leap years work and why they matter
What Is a Leap Year?
A leap year is a calendar year that contains an additional day added to keep the calendar year synchronized with the astronomical year. The Earth doesn’t orbit the Sun in exactly 365 days – it takes about 365.25 days. This extra quarter day means that, without adjustment, the calendar would slowly drift out of sync with the seasons.
To correct this drift, an extra day is added to February every four years, making it 29 days long rather than the usual 28. This adjusted year of 366 days is called a leap year.
Rules for Determining a Leap Year
The rules for calculating whether a year is a leap year are as follows:
- If the year is evenly divisible by 4, go to step 2. Otherwise, it’s not a leap year.
- If the year is evenly divisible by 100, go to step 3. Otherwise, it’s a leap year.
- If the year is evenly divisible by 400, it’s a leap year. Otherwise, it’s not a leap year.
Easy to Use
Simply enter any year and get instant results about whether it’s a leap year or not.
Detailed Explanation
Our calculator doesn’t just tell you the result—it explains why the year is or isn’t a leap year.
Educational Tool
Perfect for students, teachers, or anyone curious about how our calendar system works.
Why Leap Years Matter
Without leap years, our calendar would gradually shift relative to the Earth’s seasons. After about 100 years, the calendar would be off by 24 days. The seasons would occur at different calendar times than we expect, causing confusion in agriculture, seasonal planning, and various other aspects of life that depend on seasonal consistency.
Interesting Leap Year Facts
People born on February 29 (leap day) are sometimes called “leaplings” or “leap-year babies.” Technically, they only get to celebrate their birthday on the actual date once every four years. There are about 5 million people worldwide who were born on February 29.
In some traditions, leap years are when women can propose marriage to men—a reversal of the historical norm in which men proposed to women.
How Our Calculator Works
Our Leap Year Calculator uses JavaScript to implement the leap year algorithm. When you enter a year and click the “Check” button, the calculator determines whether it’s a leap year based on the rules mentioned above. It then provides you with a clear result and explanation of why the year qualifies or doesn’t qualify as a leap year.
Frequently Asked Questions
Common questions about leap years
A leap year is a year with 366 days instead of the regular 365 days. The extra day is added to February, making it 29 days long. This additional day helps synchronize our calendar year with the solar year (the time it takes Earth to orbit the sun).
Leap years generally occur every 4 years. However, years divisible by 100 are not leap years unless they are also divisible by 400. This means that 1900 was not a leap year, but 2000 was. The next leap year will be 2024, followed by 2028.
We need leap years to keep our calendar aligned with Earth’s revolutions around the Sun. It takes Earth approximately 365.25 days to orbit the Sun, which means our calendar would drift by about one day every four years without this adjustment. Over time, this would cause the seasons to shift significantly on the calendar.
Yes, 2000 was a leap year. Although years divisible by 100 are generally not leap years, years divisible by 400 are exceptions to this rule. Since 2000 is divisible by 400, it was a leap year with February having 29 days.
No, 2100 will not be a leap year. Although it’s divisible by 4, it’s also divisible by 100 but not by 400. According to leap year rules, such years are not leap years. The next century leap year after 2000 will be 2400.
People born on February 29 typically celebrate their birthdays on either February 28 or March 1 in non-leap years. Legally, different jurisdictions have different approaches: some consider March 1 as the legal birthday in non-leap years, while others use February 28. These individuals are sometimes called “leaplings” or “leap-year babies.”