When the Julian calendar was later refined into the Gregorian calendar in 1582, the tradition of adding a leap day to February persisted. John Tufts covers trending news for the Indianapolis Star.

The Islamic calendar is based on cycles of the moon and is used predominantly by Muslims around the world. It helps us ...

Due to the complexities of the various types of calendars, the date of Easter can be as early as March 22 and as late as April 25. Here's why.

The Gregorian calendar is an accurate measurement of time, but according to Johns Hopkins professors Steve Hanke and Richard Conn Henry, it creates a whole host of other problems.

Thursday (Feb. 29) is "leap day," an artifact that dates back to the year 46 B.C. Find out how this calendar oddity came to be.

The Gregorian calendar has 12 months, just like its predecessor, the Julian calendar. The months are January, February, March, April, May, June, July, August, September, October, November, and ...

It’s 2020 in the Gregorian calendar, but here’s what year it is in other calendars: Calendar Current year Assyrian 6770Buddhist 2563Chinese 4717Persian 1398Islamic 1441Mayan 13.0.7.5.2Hebrew 5780 ...

The switch acknowledged that even though he was born Feb. 11, 1731, according to the Julian calendar, to most of the world (which was using the Gregorian calendar), it was Feb. 22, 1732. Advertisement ...