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 3928 a leap year or a common year? When was the last leap year before 3928? When is the next leap year after 3928? Oct 08 08:41 UTC (GMT)
Is 2284 a leap year or a common year? When was the last leap year before 2284? When is the next leap year after 2284? Oct 08 08:40 UTC (GMT)
Is 1812 a leap year or a common year? When was the last leap year before 1812? When is the next leap year after 1812? Oct 08 08:39 UTC (GMT)
Is 1678 a leap year or a common year? When was the last leap year before 1678? When is the next leap year after 1678? Oct 08 08:39 UTC (GMT)
Is 1948 a leap year or a common year? When was the last leap year before 1948? When is the next leap year after 1948? Oct 08 08:39 UTC (GMT)
Is 2236 a leap year or a common year? When was the last leap year before 2236? When is the next leap year after 2236? Oct 08 08:39 UTC (GMT)
Is 3904 a leap year or a common year? When was the last leap year before 3904? When is the next leap year after 3904? Oct 08 08:38 UTC (GMT)
Is 3896 a leap year or a common year? When was the last leap year before 3896? When is the next leap year after 3896? Oct 08 08:38 UTC (GMT)
Is 3892 a leap year or a common year? When was the last leap year before 3892? When is the next leap year after 3892? Oct 08 08:38 UTC (GMT)
Is 1960 a leap year or a common year? When was the last leap year before 1960? When is the next leap year after 1960? Oct 08 08:38 UTC (GMT)
Is 4103 a leap year or a common year? When was the last leap year before 4103? When is the next leap year after 4103? Oct 08 08:37 UTC (GMT)
Is 3896 a leap year or a common year? When was the last leap year before 3896? When is the next leap year after 3896? Oct 08 08:37 UTC (GMT)
Is 4318 a leap year or a common year? When was the last leap year before 4318? When is the next leap year after 4318? Oct 08 08:37 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.