Divide the year by 4, if it is divisible, it is a leap year, if there is a remainder, it is a flat year;

2. A whole century:

Divide the year by 400. If it is divisible, it is a leap year. If there is a remainder, it is a normal year.

For example, 20 16÷4=504, so 20 16 is a leap year and 20 17 ÷ 4 = 504... 1, so 20 17 is a normal year;

2000÷400=5, so 2000 is a leap year, 1900 ÷ 400 = 4...300, so 1900 is a flat year.

The leap year in the solar calendar has 366 days and February 29 days;

The normal year of the solar calendar is 365 days, February 28th.

Calculation method:

1. leap year is a year in which ordinary years are divisible by 4 and cannot be divisible by 100. (For example, 2004 is a leap year, and 190 1 is not. )

2. Leap year can be divisible by 400 in century year. (For example, 2000 is a leap year, 1900 is not. )

Extended data:

Ordinary leap year: Gregorian calendar year is a multiple of 4, not a multiple of 100, but a leap year. (For example, 2004 is a leap year);

Century leap year: Gregorian calendar year is an integer, and it must be a multiple of 400 to be a leap year (for example, 1900 is not a century leap year, and 2000 is a century leap year);

The establishment of leap year is to make up for the time difference between the number of days in a year and the actual period of revolution of the earth caused by man-made calendar regulations. The year to make up for the time difference is leap year. Leap year * * * has 366 days (February is 1- 1 day, 29 days, 3 1 day, 30 days, 3 1 day, 3 1 day respectively).

Where there is a leap day in the solar calendar (February 29); Leap surplus (leap surplus). The time difference between the lunar calendar and the tropic year); Please note that leap year (a term in the Gregorian calendar) is not directly related to leap month (a term in the lunar calendar). The Gregorian calendar has only leap years and peace years, with 365 days in a normal year and 366 days in a leap year (one more day in February). There may also be leap months in a normal year (for example, 20 17 is a normal year, and there are leap months and leap months in the lunar calendar).

The year (non-hundred digits) can be divisible by 4 as a leap year, but it can be divisible by 4 instead of 100, but the whole hundred years (both digits are 0) must be divisible by 400 as a leap year. Everything else is a normal year.