How to calculate a leap year?

A leap year is a year with an additional day, February 29th, making it a total of 366 days instead of the usual 365 days. This adjustment helps align our calendar with the Earth's orbit around the Sun, which is about 365.2422 days long.

Here's how to calculate whether a year is a leap year or not using the leap year rules:

Divisibility by 4 Rule: The first rule is that if a year is divisible by 4, it is a potential leap year. This means years like 2004, 2008, 2012, and 2016 are leap years.

Exception for Divisibility by 100: However, there's a twist. If a year is divisible by 100, it might not be a leap year, unless it meets a certain condition.

Divisibility by 400 Exception: If a year is divisible by 400, then it's still considered a leap year, even if it's divisible by 100. This is why the year 2000 was a leap year.

Now, let's apply these rules to a few years to see if they are leap years:

2023: Is 2023 a leap year? First, check if it's divisible by 4. No, it's not divisible by 4. Therefore, 2023 is not a leap year.

1900: Is 1900 a leap year? Divisible by 4? Yes. Divisible by 100? Yes. But, not divisible by 400. So, 1900 is not a leap year.

2000: Is 2000 a leap year? Divisible by 4? Yes. Divisible by 100? Yes. Divisible by 400? Yes. So, 2000 is a leap year.

2020: Is 2020 a leap year? Divisible by 4? Yes. Divisible by 100? No. Therefore, 2020 is a leap year.

In summary, calculating a leap year involves checking its divisibility by 4, considering exceptions for divisibility by 100, and the exception to the exception – divisibility by 400. This straightforward process helps us determine whether a year has that extra day, February 29th. Always remember these rules when you're curious about whether a year is a leap year or not.