How do we calculate leap year?

When an extra day is added with the shortest month of the year that is February, that year is to be considered as a leap year. February 29, is famously considered to be a leap year. This happens after every 4 years of gap. Instead of having 365 days in a year, the leap year has 366 days. The way by which we can calculate leap years is that the year has to be divided by 4. Leap year can also be calculated when it is evenly divided by 400.