Determine if any year is a leap year and discover upcoming leap years. A leap year occurs every 4 years, with exceptions for century years that aren't divisible by 400.
Leap Year Rules
Divisible by 4: A year must be divisible by 4 to be a leap year (e.g., 2020, 2024)
Century Exception: If the year is a century year (divisible by 100), it must also be divisible by 400 to be a leap year (e.g., 2000 was a leap year, but 1900 was not)
Purpose: Leap years help synchronize the calendar year with the astronomical year, which is approximately 365.25 days long
How to Use This Tool
Enter any year (from 1 to 9999) in the input field
Click "Check Leap Year" to see if it's a leap year
View the next 10 upcoming leap years from your entered year
Review the leap year rules to understand the calculation logic
Understanding Leap Years
A leap year is a calendar year that contains an additional day (February 29th) to keep the calendar year synchronized with the astronomical year. The Earth takes approximately 365.25 days to orbit the Sun, so adding an extra day every four years helps compensate for this difference.
Without leap years, our calendar would gradually drift out of sync with the seasons. Over centuries, this would cause significant seasonal shifts, affecting agriculture, weather patterns, and cultural celebrations tied to specific dates.
Examples
2024: Leap year (divisible by 4)
2023: Not a leap year (not divisible by 4)
2000: Leap year (divisible by 400)
1900: Not a leap year (divisible by 100 but not by 400)