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# Leap year tester

World's simplest time tool
With this browser-based application, you can check if a given calendar year is a leap year. You can enter one or many different years into the input field with one date per line and get the answer to the test question of whether the given year is a leap year. Created by computer nerds from team Browserling.
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## What is a leap year tester?

This is a quick online utility for testing if the given year is a leap year. Just as a reminder, a leap year has 366 days, which is one more day than a common year. This extra day is added to the month of February and it falls on February 29th. There's a simple mathematical formula for calculating if the given year is a leap year. Leap years are those years that are divisible by 4 but not divisible by 100, as well as years that are divisible by 100 and 400 simultaneously. Our algorithm checks each input year using this formula and outputs the year's status. For example, if you enter the value "2025" as input, the program will display "2025 is not a leap year.", and for the value "2028", the status will be "2028 is a leap year.". You can also enter multiple years as the input in a column and get a matching column of statuses as the output. Timeabulous!

## Leap year tester examples

Click to use
Find Birthdays on February 29
One of our friends was born on a leap year on February 29th and as a consequence, she has a birthday only once every 4 years. As we can never really remember when her birthday is, we are using our program to create a reminder list of the upcoming leap years. To create a list of her next birthdays, we load a sequence of years from 2025 to 2040 into the input and get the status of each year. If the program says that it's a leap year, then we know that we'll be invited to a birthday party on February 29th.
2025 2026 2027 2028 2029 2030 2031 2032 2033 2034 2035 2036 2037 2038 2039 2040
2025 is not a leap year. 2026 is not a leap year. 2027 is not a leap year. 2028 is a leap year. 2029 is not a leap year. 2030 is not a leap year. 2031 is not a leap year. 2032 is a leap year. 2033 is not a leap year. 2034 is not a leap year. 2035 is not a leap year. 2036 is a leap year. 2037 is not a leap year. 2038 is not a leap year. 2039 is not a leap year. 2040 is a leap year.
Check a List of Leap Years
In this example, we're working with a list of leap years that we found on the Internet. As you can never really believe the information you find on the Internet, we decided to independently check the correctness of this list with our leap year checker. After loading the list into the input area, we instantly noticed that there was an error! The year 2078 is not a leap year (it should be 2076 instead).
2052 2056 2060 2064 2068 2072 2078 2080 2084 2088 2092 2096
2052 is a leap year. 2056 is a leap year. 2060 is a leap year. 2064 is a leap year. 2068 is a leap year. 2072 is a leap year. 2078 is not a leap year. 2080 is a leap year. 2084 is a leap year. 2088 is a leap year. 2092 is a leap year. 2096 is a leap year.
Pro tips Master online time tools
You can pass input to this tool via ?input query argument and it will automatically compute output. Here's how to type it in your browser's address bar. Click to try!
https://onlinetimetools.com/check-leap-year?input=2025%0A2026%0A2027%0A2028%0A2029%0A2030%0A2031%0A2032%0A2033%0A2034%0A2035%0A2036%0A2037%0A2038%0A2039%0A2040
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