The Julian day count, which differs from the Julian calendar, was proposed by Joseph Justus Scaliger in the 16th century and named after his father, Julius Caesar Scaliger. According to the Julian calendar the count was initiated on 1st January 4713 BC, at noon. The starting point according to the Gregorian calendar is 24 November of the year 4714 BC, at noon. The Julian calendar takes 365.25 days to complete its yearly cycle, while the solar year only takes 365.2422 days. In 1582, Pope Gregory XIII introduced the Gregorian calendar as a substitute for the Julian calendar.

Under certain conditions, a year will take 365.2425 days by skipping leap years. North Africa, including the Canary Islands, marks the end of the year on 13 January (14 January in 2101) to welcome the new year the following day. The Amazigh new year starts on the first day of the month Yennayer. The way the Amazigh calendar divides the year into days and months is similar to the Julian calendar. The Amazigh date is approximately 900 years ahead of the Julian calendar introduced by Julius Caesar in 46 BC. This date is linked to the reign of the Libyan dynasty.