How to distinguish between leap years and common years? Actually, the difference between leap years and common years is very simple, and there are several methods to distinguish them. The introduction of the method to judge leap years is on Huayi Network. After reading this article, you will know how to distinguish between leap years and common years.

How to distinguish between leap years and common years

Method One:
Generally, a year that can be divided by 4 is a leap year, and a year that cannot be divided by 4 is a common year. For example, 1988 and 2008 are leap years, while 2005, 2006, and 2007 are common years.
Method Two:
If it is a century year (i.e., a whole hundred year), then it is only a leap year if it can be divided by 400; otherwise, it is a common year. For example, 2000 is a leap year, while 1900 is a common year.
Method Three:
Just look at February of the current year. A leap year has 29 days in February, while a common year has only 28 days.
Method Four:
Look at the last two digits of the year. If the last two digits can be divided by 4, then it is a leap year; otherwise, it is not.

Introduction to the method of judging leap years

Method of judging leap years:
If it is a multiple of 4, the year is generally a leap year; if it is not a multiple of 4, the year is generally a common year. For Gregorian calendar years that are multiples of 100, they must be multiples of 400 to be leap years; otherwise, they are common years.
The Earth's orbit around the Sun takes 365 days, 5 hours, 48 minutes, and 46 seconds (equivalent to 365.24219 days), which is one tropical year. The common year in the Gregorian calendar has only 365 days, which is about 0.2422 days shorter than the tropical year. The remaining time accumulates to about one day every four years, so an extra day is added to the end of February in the fourth year, making the length of that year 366 days, and this year is called a leap year.
In the current Gregorian calendar, there are 97 leap years in 400 years. According to the calculation of one leap year every four years, an average of 0.0078 days is added each year. Over 400 years, this would accumulate to about three days. Therefore, three leap years need to be reduced every 400 years. Thus, the Gregorian calendar stipulates: when the year is a multiple of 100, it must be a multiple of 400 to be a leap year; otherwise, even if it is a multiple of 4, it is not a leap year.