About this days in month tool
Months have 28, 29, 30, or 31 days. April, June, September, and November have 30; February has 28, or 29 in a leap year; all the others have 31. Leap years follow the Gregorian rule: a year divisible by 4 is a leap year, except years divisible by 100, which are only leap years when also divisible by 400. So 2000 was a leap year but 1900 was not. This tool applies that rule to any year from 1 to 9999, shows the month as a calendar, counts its weekdays and weekend days, and lists the length of every month in the year.
How to find the days in a month
- Enter the year. Type any year from 1 to 9999, or press one of the example years.
- Choose the month. Pick it from the list or press its short name.
- Press Count days. Read the number of days, the weekday count, the leap-year note, and the calendar.
Frequently asked questions
Which months have 31 days?
January, March, May, July, August, October, and December have 31 days. A common rhyme starts “Thirty days hath September, April, June, and November”.
How many days does February have?
February has 28 days in common years and 29 in leap years, such as 2024 and 2028. It is the only month whose length changes.
Why was 1900 not a leap year?
Century years are leap years only when they divide evenly by 400. 1900 does not, so it had 365 days, while 2000 does and had 366.
What is the knuckle trick?
Count the months across your knuckles and the gaps between them. Months that land on a knuckle have 31 days; those in a gap have 30, except February.
How many days are in a year?
A common year has 365 days and a leap year has 366. Over a 400-year cycle the average is 365.2425 days, very close to the solar year.