Time & Dates

What Is a Leap Year?

A leap year is a year with 366 days instead of 365, with February 29 added to keep the calendar aligned with Earth's orbit around the Sun, which takes about 365.2422 days. In the Gregorian calendar, a year is a leap year if it is divisible by 4, except century years, which must also be divisible by 400.

Examples

2024 and 2028 are leap years. 1900 was not, because it is divisible by 100 but not by 400; 2000 was, because it is divisible by 400.

🧮 Calculate It Yourself

Put Leap Year into practice with these free calculators — no sign-up, nothing stored.

📅 Date Calculator Find days between two dates, or add/subtract days from a date. Calculate → 🎂 Age Calculator Find your exact age in years, months, and days. Calculate → 📆 Week Number Calculator ISO 8601 and US week numbers for any date, and the dates of any week. Calculate →

🔗 Related Terms

Day of the Year ISO Week Number Chronological Age

More Time & Dates Terms

📖 Browse all glossary terms or explore all free calculators.

Last updated: September 27, 2026. This definition is for general educational purposes only. It is not financial, investment, tax, legal, or medical advice, and it does not recommend any product or course of action. For decisions about your own situation, consult a qualified professional.