Leap Years Calculator. It also calculates the last leap year that was before a year and the next leap year that is after a year. The leap year algorithm. A leap year has 366 days, one extra day (Feb 29) over a normal year. There are 97 leap years every 400 years

Is it a leap year? The last and the next leap year, before and after the year

The leap year algorithm. The three conditions to check in order to know whether a year is a leap or a common one:

1) A year that is divisible by 4 (no remainder when divided by 4) is a leap year.

2) But if the year is also divisible by 100 (no remainder when divided by 100), it's not a leap year, unless....

3) ... Unless it's divisible by 400 (no remainder when divided by 400).

Latest checked up years / Is it a leap year or a common year?

Is 2100 a leap year or a common year? When was the last leap year before 2100? When is the next leap year after 2100? Dec 03 14:37 UTC (GMT)
Is 2000 a leap year or a common year? When was the last leap year before 2000? When is the next leap year after 2000? Dec 03 14:35 UTC (GMT)
Is 1661 a leap year or a common year? When was the last leap year before 1661? When is the next leap year after 1661? Dec 03 14:35 UTC (GMT)
Is 2072 a leap year or a common year? When was the last leap year before 2072? When is the next leap year after 2072? Dec 03 14:34 UTC (GMT)
Is 1907 a leap year or a common year? When was the last leap year before 1907? When is the next leap year after 1907? Dec 03 14:34 UTC (GMT)
Is 3588 a leap year or a common year? When was the last leap year before 3588? When is the next leap year after 3588? Dec 03 14:34 UTC (GMT)
Is 3360 a leap year or a common year? When was the last leap year before 3360? When is the next leap year after 3360? Dec 03 14:34 UTC (GMT)
Is 1858 a leap year or a common year? When was the last leap year before 1858? When is the next leap year after 1858? Dec 03 14:33 UTC (GMT)
Is 2023 a leap year or a common year? When was the last leap year before 2023? When is the next leap year after 2023? Dec 03 14:32 UTC (GMT)
Is 2300 a leap year or a common year? When was the last leap year before 2300? When is the next leap year after 2300? Dec 03 14:30 UTC (GMT)
Is 3027 a leap year or a common year? When was the last leap year before 3027? When is the next leap year after 3027? Dec 03 14:29 UTC (GMT)
Is 2916 a leap year or a common year? When was the last leap year before 2916? When is the next leap year after 2916? Dec 03 14:27 UTC (GMT)
Is 1955 a leap year or a common year? When was the last leap year before 1955? When is the next leap year after 1955? Dec 03 14:25 UTC (GMT)
All the users checked up years / Leap Years or Common Years

Leap Years. Common Years. What are they and why do we need them? The leap years algorithm.

What is a leap year? What is a common year?

A leap year contains 1 extra day, February 29th, over an ordinary year, 366 vs. 365.

How often do the leap years occur in the calendar?

Nearly once every four years, 97 leap years at every 400 years.

Why do we need leap years?

They keep the calendar year synchronized with the astronomical year, preventing us, for example, from celebrating Christmas in November.

The leap years algorithm.

Every year that is evenly divisible by 4 is a leap year, except for years that are evenly divisible by 100, but these years are leap years if they are evenly divisible by 400:

Examples of leap years.

  • Leap years multiples of 4 but not of 100 nor of 400: 1992, 1996, 2004, 2008, 2012, 2016, 2020, 2024, 2028;
  • Common years (NOT LEAP YEARS) multiples of 100, but not of 400: 1700, 1800, 1900, 2100, 2200, 2300;
  • Leap years multiples of 400: 1600, 2000, 2400.

Articles on the leap years

1. What is a leap year? What is a common year?

2. How often do the leap years occur in the calendar?

3. Why do we need leap years?

4. Leap years algorithm. Examples.

5. When did the actual concept of the leap year originate?

6. The modern (Gregorian) calendar and the Julian one. Julian calendar adjustment

7. How accurate is the Gregorian calendar, based on the leap year algorithm?


List of all the leap years between 1582 and 4818.