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 1935 a leap year or a common year? When was the last leap year before 1935? When is the next leap year after 1935? Jul 15 01:50 UTC (GMT)
Is 2620 a leap year or a common year? When was the last leap year before 2620? When is the next leap year after 2620? Jul 15 01:49 UTC (GMT)
Is 2620 a leap year or a common year? When was the last leap year before 2620? When is the next leap year after 2620? Jul 15 01:49 UTC (GMT)
Is 1641 a leap year or a common year? When was the last leap year before 1641? When is the next leap year after 1641? Jul 15 01:46 UTC (GMT)
Is 2020 a leap year or a common year? When was the last leap year before 2020? When is the next leap year after 2020? Jul 15 01:46 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? Jul 15 01:46 UTC (GMT)
Is 2123 a leap year or a common year? When was the last leap year before 2123? When is the next leap year after 2123? Jul 15 01:45 UTC (GMT)
Is 2140 a leap year or a common year? When was the last leap year before 2140? When is the next leap year after 2140? Jul 15 01:45 UTC (GMT)
Is 2752 a leap year or a common year? When was the last leap year before 2752? When is the next leap year after 2752? Jul 15 01:44 UTC (GMT)
Is 1954 a leap year or a common year? When was the last leap year before 1954? When is the next leap year after 1954? Jul 15 01:42 UTC (GMT)
Is 2716 a leap year or a common year? When was the last leap year before 2716? When is the next leap year after 2716? Jul 15 01:38 UTC (GMT)
Is 1952 a leap year or a common year? When was the last leap year before 1952? When is the next leap year after 1952? Jul 15 01:37 UTC (GMT)
Is 1582 a leap year or a common year? When was the last leap year before 1582? When is the next leap year after 1582? Jul 15 01:37 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.