Gregorian calendar
About the Gregorian calendar
The Gregorian calendar is the civil calendar of nearly the whole world. Introduced by Pope Gregory XIII in 1582, it keeps the Julian pattern of a leap year every four years but drops three leap days every 400 years: century years are leap years only if divisible by 400. Its mean year of 365.2425 days drifts from the tropical year by roughly one day in 3000 years.
Related Entries
Bahá'í calendar
1844 epoch; reformed...The Badí' calendar of the Bahá'í Faith, created by the Báb and adopted by Bahá'u'lláh, has 19 months of 19 days plus four or five...
International Fixed Calendar
Proposed 1902Moses Cotsworth proposed a perpetual calendar of 13 months of exactly 28 days, with a new month, Sol, between June and July and...
World Calendar
Proposed 1930Elisabeth Achelis promoted the World Calendar from 1930: four identical quarters of 91 days with months of 31, 30 and 30 days...
ISO week date
1988 (ISO 8601)The ISO week date in ISO 8601, first published in 1988, numbers weeks from Monday to Sunday. Week 1 is the week containing the...