A common year starting on Friday is any non-

leap year A leap year (also known as an intercalary year or bissextile year) is a calendar year that contains an additional day (or, in the case of a lunisolar calendar, a month) added to keep the calendar year synchronized with the astronomical year or s ...

(i.e. a year with 365 days) that begins on

Friday Friday is the day of the week between Thursday and Saturday. In countries that adopt the traditional "Sunday-first" convention, it is the sixth day of the week. In countries adopting the ISO-defined "Monday-first" convention, it is the fifth d ...

, 1 January, and ends on Friday, 31 December. Its

dominical letter Dominical letters or Sunday letters are a method used to determine the day of the week for particular dates. When using this method, each year is assigned a letter (or pair of letters for leap years) depending on which day of the week the year star ...

hence is C. The most recent year of such kind was

2021 File:2021 collage V2.png, From top left, clockwise: the James Webb Space Telescope was launched in 2021; Protesters in Yangon, Myanmar following the 2021 Myanmar coup d'état, coup d'état; A civil demonstration against the October–November 2021 ...

and the next one will be 2027 in the

Gregorian calendar The Gregorian calendar is the calendar used in most parts of the world. It was introduced in October 1582 by Pope Gregory XIII as a modification of, and replacement for, the Julian calendar. The principal change was to space leap years dif ...

, or, likewise,

2011 File:2011 Events Collage.png, From top left, clockwise: a protester partaking in Occupy Wall Street heralds the beginning of the Occupy movement; protests against Libyan dictator Muammar Gaddafi, who was killed that October; a young man celebrate ...

2022 File:2022 collage V1.png, Clockwise, from top left: Road junction at Yamato-Saidaiji Station several hours after the assassination of Shinzo Abe; 2022 Sri Lankan protests, Anti-government protest in Sri Lanka in front of the Presidential Secretari ...

and 2033 in the obsolete

Julian calendar The Julian calendar, proposed by Roman consul Julius Caesar in 46 BC, was a reform of the Roman calendar. It took effect on , by edict. It was designed with the aid of Greek mathematicians and astronomers such as Sosigenes of Alexandr ...

, see below for more. This common year is one of the three possible common years in which a century year can begin on, and occurs in century years that yield a remainder of 100 when divided by 400. The most recent such year was 1700 and the next one will be 2100. Any common year that starts on Wednesday,

Saturday Saturday is the day of the week between Friday and Sunday. No later than the 2nd century, the Romans named Saturday ("Saturn's Day") for the planet Saturn, which controlled the first hour of that day, according to Vettius Valens. The day ...

has only one Friday the 13th: the only one in this common year occurs in August. Leap years starting on Thursday share this characteristic, but also have another one in February. In this common year, February is rectangular where weeks start on Monday,

Martin Luther King Jr. Day Martin Luther King Jr. Day (officially Birthday of Martin Luther King, Jr., and sometimes referred to as MLK Day) is a federal holiday in the United States marking the birthday of Martin Luther King Jr. It is observed on the third Mond ...

is on

January 18 Events Pre-1600 * 474 – Seven-year-old Leo II succeeds his maternal grandfather Leo I as Byzantine emperor. He dies ten months later. * 532 – Nika riots in Constantinople fail. * 1126 – Emperor Huizong abdicates the Chi ...

Valentine’s Day Valentine's Day, also called Saint Valentine's Day or the Feast of Saint Valentine, is celebrated annually on February 14. It originated as a Christian feast day honoring one or two early Christian martyrs named Saint Valentine and, thro ...

is on a

Sunday Sunday is the day of the week between Saturday and Monday. In most Western countries, Sunday is a day of rest and a part of the weekend. It is often considered the first day of the week. For most observant adherents of Christianity, Sunday ...

Presidents Day Presidents' Day, also called Washington's Birthday at the federal governmental level, is a holiday in the United States celebrated on the third Monday of February to honor all persons who served as presidents of the United States and, since 1879 ...

is on its earliest possible date,

February 15 Events Pre-1600 * 438 – Roman emperor Theodosius II publishes the law codex Codex Theodosianus * 590 – Khosrau II is crowned king of Persia. * 706 – Byzantine emperor Justinian II has his predecessors Leontios and Tiberi ...

St. Patrick’s Day Saint Patrick's Day, or the Feast of Saint Patrick ( ga, Lá Fhéile Pádraig, lit=the Day of the Festival of Patrick), is a cultural and religious celebration held on 17 March, the traditional death date of Saint Patrick (), the foremost pat ...

is on a

Wednesday Wednesday is the day of the week between Tuesday and Thursday. According to international standard ISO 8601, it is the third day of the week. In countries which have Friday as their holiday, Wednesday is the fifth day of the week. In countrie ...

Memorial Day Memorial Day (originally known as Decoration Day) is a federal holiday in the United States for mourning the U.S. military personnel who have fought and died while serving in the United States armed forces. It is observed on the last Monda ...

is on its latest possible date,

May 31 Events Pre-1600 * 455 – Emperor Petronius Maximus is stoned to death by an angry mob while fleeing Rome. * 1223 – Mongol invasion of the Cumans: Battle of the Kalka River: Mongol armies of Genghis Khan led by Subutai defeat K ...

Juneteenth Juneteenth is a federal holiday in the United States commemorating the emancipation of enslaved African Americans. Deriving its name from combining "June" and "nineteenth", it is celebrated on the anniversary of General Order No. 3, i ...

is on a

U.S. Independence Day Independence Day (colloquially the Fourth of July) is a federal holiday in the United States commemorating the Declaration of Independence, which was ratified by the Second Continental Congress on July 4, 1776, establishing the United States ...

and

Halloween Halloween or Hallowe'en (less commonly known as Allhalloween, All Hallows' Eve, or All Saints' Eve) is a celebration observed in many countries on 31 October, the eve of the Western Christian feast of All Saints' Day. It begins the observanc ...

are on Sunday, Labor Day is on

September 6 Events Pre-1600 * 394 – Battle of the Frigidus: Roman emperor Theodosius I defeats and kills Eugenius the usurper. His Frankish ''magister militum'' Arbogast escapes but commits suicide two days later. *1492 – Christopher Colu ...

Thanksgiving Thanksgiving is a national holiday celebrated on various dates in the United States, Canada, Grenada, Saint Lucia, Liberia, and unofficially in countries like Brazil and Philippines. It is also observed in the Netherlander town of Leiden ...

is on

November 25 Events Pre-1600 *571 BC – Servius Tullius, king of Rome, celebrates the first of his three triumphs for his victory over the Etruscans. *1034 – Máel Coluim mac Cináeda, King of Scots, dies. His grandson, Donnchad, son of Bethó ...

, and

Christmas Christmas is an annual festival commemorating Nativity of Jesus, the birth of Jesus, Jesus Christ, observed primarily on December 25 as a religious and cultural celebration among billions of people Observance of Christmas by country, around t ...

is on a

Calendars

This is the only year type where the ''n''th "

Doomsday Doomsday may refer to: * Eschatology, a time period described in the eschatological writings in Abrahamic religions and in doomsday scenarios of non-Abrahamic religions. * Global catastrophic risk, a hypothetical event explored in science and fict ...

" (this year Sunday) is not in ISO week ''n''; it is in ISO week ''n''-1.

Applicable years

Gregorian calendar

In the (currently used) Gregorian calendar, alongside

Monday Monday is the day of the week between Sunday and Tuesday. According to the International Organization for Standardization's ISO 8601 standard, it is the first day of the week and in countries that adopt the "Sunday-first" convention, it is t ...

, the fourteen types of year (seven common, seven leap) repeat in a 400-year cycle (20871 weeks). Forty-three common years per cycle or exactly 10.75% start on a Friday. The 28-year sub-cycle only spans across century years divisible by 400, e.g. 1600, 2000, and 2400. 400 year cycle: *century 1: 010, 021, 027, 038, 049, 055, 066, 077, 083, 094, 100 *century 2: 106, 117, 123, 134, 145, 151, 162, 173, 179, 190 *century 3: 202, 213, 219, 230, 241, 247, 258, 269, 275, 286, 297 *century 4: 309, 315, 326, 337, 343, 354, 365, 371, 382, 393, 399

Julian calendar

In the now-obsolete Julian calendar, the fourteen types of year (seven common, seven leap) repeat in a 28-year cycle (1461 weeks). This sequence occurs exactly once within a cycle, and every common letter thrice. As the Julian calendar repeats after 28 years that means it will also repeat after 700 years, i.e. 25 cycles. The year's position in the cycle is given by the formula ((year + 8) mod 28) + 1). Years 4, 15 and 26 of the cycle are common years beginning on Friday. 2017 is year 10 of the cycle. Approximately 10.71% of all years are common years beginning on Friday.

References

{{DEFAULTSORT:Common Year Starting On Friday Gregorian calendar Julian calendar Friday