As you’re nearing the end of February, dates can get confusing. The irregular month, already unique in its 28-day length, sometimes has a 29th day, also known as Leap Day.
This is even worse for the 5 million people with Leap Day birthdays, according to a History estimate, whose real birthdays come only once every four years.
This phenomenon may cause you a small inconvenience, but leap years are not just a cruel trick calendar companies play to keep you guessing. There’s actually a very good astronomical reason for the added day — but we’ll get into that later.
When is the next leap year?
Generally speaking, leap years come every four years: 2024, 2028 and 2032, for example, will all be leap years.
Usually, if a year is divisible by 4, that makes it a leap year, but this rule does not hold for years which are multiples of one hundred, according to History.com. Although the Earth’s orbit around the sun was previously thought to be 365.25 days, it actually takes closer to 365.24 days says History.com.
To fix this small discrepancy, century years which are not divisible by 400 are not leap years. The year 2000 was a leap year, but the year 2100 will not be.
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Why do we have leap years?
Because the amount of time the Earth takes to spin on its axis is not dependent on the amount of time the Earth takes to complete a full orbit around the sun, the number of 24-hour rotations that fit into a calendar year is not a whole number.
According to History, a leap year is the solution to this. Just one extra day every four years keeps our calendar lined up correctly with the orbit of the Earth, meaning winter stays winter, and summer stays summer.
How many days are in a leap year?
There are 366 days in a leap year — one more than the typical 365-day year.
When was the last leap year?
Until 2024, 2020 would have been the most recent leap year.
These are the weirdest Leap Day myths
01:06 - Source: CNN
CNN —
Here’s a look at leap year. 2024 is a leap year. The next leap day is February 29, 2024, on a Thursday.
But why do we even have leap years?
Our calendar has 365 days in a year, because that’s pretty much how long it takes the Earth to orbit the Sun. The problem is that in reality it takes the Earth around 365 ¼ days (actually 365.24219 days) to circle the Sun (that’s a solar year), which means our calendar is out by around a quarter of a day a year.
That discrepancy was spotted a while back.
In 45 B.C. a decree by Julius Caesar began the practice of adding an extra day every four years, with the creation of the Julian calendar – making up for those quarter days.
That would be perfect if a solar year were exactly 365 ¼ days – but 365.242 is a teeny bit less than that, and over time that teeny bit adds up.
By 1582 A.D. that slight discrepancy in the Julian calendar added up to 10 days. So Pope Gregory XIII created the Gregorian calendar, coined the term “leap year” and established February 29 as the official date to add to a leap year. He also introduced a rule to take into account the discrepancy in the Julian calendar.
Now, a leap year occurs in every year that is divisible by four, but only in century years that are evenly divided by 400.
Therefore, 800, 1200 and 2000 were leap years - but 1700 and 1900 were not, because even though they are divisible by four, they are not divisible by 400.
So that fixes everything, right?
Well, not entirely. The solar year is approximately 26 seconds shorter than the Gregorian year at the moment – but that’s a problem for another day.
To check if any year is a leap year, please type a year number in the form below then click on the button 'Is Leap a Year?'.
What is Leap Year and How Many Days Do you Have in a Leap Year?
A leap year has a total of 366 days instead of the usual 365 as a result of adding an extra day (February 29) to the Gregorian Calendar which is the calendar currently used by most modern societies. This calendar was introduced in 1582, to replace the flawed Julian Calendar.
How to Know if Certain Year is a Leap Year
The 3 conditions for a given year be a leap year are:
- The year is exactly divisible by four (with no reminder);
- If the year is divisible by 100 (years ending in two zeros), it is not a leap, except if
- It is also divisible by 400 (in this case it will be a leap year).
Examples:
Was 2000 a leap year?
- 2000 is divisible 4 (2000/4 = 500). Therefore, it could be a leap year.
- 2000 is divisible by 100 (2000/100 = 20), So, it could not have been a leap year, but
- 2000 is divisible 400 ( 2000/400 = 5). So, we conclude that 2000 was a leap year.
Will 2020 be a leap year?
- 2020 is divisible 4 (= 505). So it could be a leap year
- 2020 is not divisible by 100 (= 20.2), so it will be a leap year. (It is not necessary to check the third condition)
Will 2018 be leap year?
- 2018 is not divisible 4 (= 504.5), so it will not be a leap year (it is not necessary to check the next two conditions).
The year being divisible by 4 is a necessary condition, but not sufficient for a year to be leap, but for this century, we may consider sufficient until the year 2098. For this century, is not necessary to check the other conditions. So, we can surely say that: "until 2096, if we want to know if a given year is leap or not, we just need to check if thath year is or is not divisible by 4. So, any year divisible by four is a leap year! (for this centuty).
The leap year system makes the calendar coincide with the cycle of the seasons.
When's the next leap year?
The next leap years until 2098 will be:
2020, 2024, 2028, 2032, 2036, 2040, 2044, 2048, 2052, 2056, 2060, 2064, 2068, 2072, 2076, 2080, 2084, 2088, 2092 e 2096
Leap year List from 1600 to 2100
1600 | 1696 | 1796 | 1896 | 1996 |
1604 | 1704 | 1804 | 1904 | 2000 |
1608 | 1708 | 1808 | 1908 | 2004 |
1612 | 1712 | 1812 | 1912 | 2008 |
1616 | 1716 | 1816 | 1916 | 2012 |
1620 | 1720 | 1820 | 1920 | 2016 |
1624 | 1724 | 1824 | 1924 | 2020 |
1628 | 1728 | 1828 | 1928 | 2024 |
1632 | 1732 | 1832 | 1932 | 2028 |
1636 | 1736 | 1836 | 1936 | 2032 |
1640 | 1740 | 1840 | 1940 | 2036 |
1644 | 1744 | 1844 | 1944 | 2040 |
1648 | 1748 | 1848 | 1948 | 2044 |
1652 | 1752 | 1852 | 1952 | 2048 |
1656 | 1756 | 1856 | 1956 | 2052 |
1660 | 1760 | 1860 | 1960 | 2056 |
1664 | 1764 | 1864 | 1964 | 2060 |
1668 | 1768 | 1868 | 1968 | 2064 |
1672 | 1772 | 1872 | 1972 | 2068 |
1676 | 1776 | 1876 | 1976 | 2072 |
1680 | 1780 | 1880 | 1980 | 2076 |
1684 | 1784 | 1884 | 1984 | 2080 |
1688 | 1788 | 1888 | 1988 | 2084 |
1692 | 1792 | 1892 | 1992 | 2088 |
- | - | - | - | 2092 |
- | - | - | - | 2096 |
Note: 2100 will not be a leap year.
Click on any year below to check if it is a leap year: