Leap Year Math
A Leap Year Comes Around Every Four Years
Although it takes 365 and a ¼ days for earth to travel around the sun, we only actually see 365 days every non-leap year.
Every four years, we accumulate a full day ( ¼ + ¼ + ¼ + ¼ = 1 day) that was not accounted for in our three previous calendar years. Therefore, the accrued day is observed every four years, known as a leap year.
On a leap year, like this year 2020, we will see an additional day added to our calendars on February 29th.
Leap Year Math
Have you ever wondered if your birth year was a leap year, or if your parents and grandparents were born on a leap year?
According to the Gregorian Calendar, there are three factors needed to identify leap years:
- The year can be divided by 4 evenly;
- If the year can be divided by 100 evenly, then it is NOT a leap year, unless;
- The year is divisible by 400.
If these apply, then the year is a leap year.
Here’s our easy flow chart to help you analyze whether a particular year was/will be a leap year or not.

TEST IT OUT.
A. Was the year 1290 a leap year?
B. Was the year 2000 a leap year?
C. When is the next leap year after 2020?

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