Check if any year is a leap year, understand the leap year rules, and see a list of upcoming leap years.
Enter any year to check if it's a leap year
A leap year is a year with 366 days instead of the usual 365. The extra day, February 29th (called "leap day"), is added to keep our calendar synchronized with Earth's orbit around the Sun, which takes approximately 365.25 days.
Without leap years, our calendar would slowly drift out of sync with the seasons — about 24 days every 100 years. Over centuries, this would mean summer eventually occurring in December!
Leap Year Rules (Gregorian Calendar):
Examples: 2024 is a leap year (divisible by 4). 1900 was not a leap year (divisible by 100 but not 400). 2000 was a leap year (divisible by 400).
Type any year from 1 to 9999. The calculator automatically checks the current year when you first load the page.
The calculator instantly shows whether the year is a leap year, how many days it has, and when the previous and next leap years occur.
The calculator also displays the next 10 leap years for planning birthdays, anniversaries, or other special leap day events.
Check: Is 2024 a leap year?
Calculation:
Check: Is 1900 a leap year?
Calculation:
Check: Is 2000 a leap year?
Calculation:
Earth takes approximately 365.2422 days to orbit the Sun, not exactly 365 days. Without leap years, our calendar would drift by about 0.2422 days per year. After 100 years, this would accumulate to 24.22 days — nearly a full month! Leap years keep our calendar aligned with the seasons.
People born on February 29 are called "leaplings" or "leapers." They only get a true birthday once every 4 years! In non-leap years, most leaplings celebrate on February 28 or March 1. Legally, many jurisdictions consider them to "age" on March 1 in non-leap years.
Julius Caesar introduced the Julian calendar in 45 BCE with a leap year every 4 years. However, this was slightly too many leap years. Pope Gregory XIII refined it in 1582 with the Gregorian calendar, adding the 100-year and 400-year rules to make it more accurate.
The current system is accurate to about 1 day in 3,236 years. Eventually, a correction might be needed — possibly skipping a leap year in the year 4000 or 4800. However, Earth's rotation is gradually slowing, which complicates long-term predictions.
In Ireland and Britain, there's a tradition that women can propose to men on leap day. Some cultures consider leap years lucky, while others see them as unlucky. In Greece, it's considered unlucky to marry during a leap year!
The year 2100 will NOT be a leap year (divisible by 100 but not 400). The next century leap year after 2000 will be 2400 — 376 years after the most recent one!
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