What Is a Leap Year?
Nearly every four years is a leap year which has 366 days, as opposed to a common year, which has 365.
When Is the Next Leap Year?
Next leap day is February 29, 2016.
Why Add Leap Years?
Leap years are needed to keep our modern day Gregorian calendar in alignment with the Earth's revolutions around the sun.
It takes the Earth approximately 365.242189 days – or 365 days, 5 hours, 48 minutes, and 45 seconds – to circle once around the Sun. This is called a tropical year.
However, the Gregorian calendar has only 365 days in a year, so if we didn't add a leap day on February 29 nearly every four years, we would lose almost six hours off our calendar every year. After only 100 years, our calendar would be off by around 24 days!
Exactly Which Years Are Leap Years?
In the Gregorian calendar three criteria must be taken into account to identify leap years:
- The year can be evenly divided by 4;
- If the year can be evenly divided by 100, it is NOT a leap year, unless;
- The year is also evenly divisible by 400. Then it is a leap year.
Special Leap Year 2000
Who Invented Leap Years?
Roman general Julius Caesar introduced the first leap years over 2000 years ago. But the Julian calendar had only one rule: any year evenly divisible by four would be a leap year.
This formula produced way too many leap years, but was not corrected until the introduction of the Gregorian calendar more than 1500 years later.
Leap Days 2016 – 2032
|Year||February 29 – Day of the Week|
Leap Day Library
- Leap Day is February 29
- Customs & Traditions
- Common Year vs. Leap Year
- Born on Leap Day
- February 30 Was a Real Date
What is a Leap Year?
Alternative Leap Years
- Bahá'í Leap Year
- Chinese Leap Year
- Ethiopian leap year
- The Hindu leap year
- The Iranian Leap Year
- The Islamic leap year
- The Jewish Leap Year
- The Gregorian Calendar
- The Julian Calendar
- The Revised Julian Calendar
- The Mayan Calendar
- The Chinese Calendar
- The Roman Calendar
- Switch from Julian to Gregorian
- Is There a Perfect Calendar?