A decimal calendar is a calendar which includes

units of time A unit of time is any particular time interval, used as a standard way of measuring or expressing duration. The SI base unit, base unit of time in the International System of Units (SI), and by extension most of the Western world, is the second, ...

based on the decimal system. For example, a "decimal month" would consist of a year with 10 months and 36.52422 days per month.

History

Egyptian calendar

The ancient Egyptian calendar consisted of twelve months, each divided into three weeks of ten days, with five intercalary days.

Calendar of Romulus

The original Roman calendar consisted of ten months; however, the calendar year only lasted 304 days, with 61 days during winter not assigned to any month. The months of

Ianuarius , ("January"), or in full , abbreviated , was the first month of the Roman calendar, ancient Roman calendar, from which the Julian calendar, Julian and Gregorian calendar, Gregorian month of January derived. It was followed by ''Februarius'' (" ...

and

Februarius ''Februarius'', fully ''Mensis Februarius'' ("month of Februa"), was the shortest month of the Roman calendar from which the Julian calendar, Julian and Gregorian calendar, Gregorian month of February derived. It was eventually placed second in ...

were added to the calendar by

Numa Pompilius Numa Pompilius (; 753–672 BC; reigned 715–672 BC) was the Roman mythology, legendary second king of Rome, succeeding Romulus after a one-year interregnum. He was of Sabine origin, and many of Rome's most important religious and political ins ...

in 700 BCE.

French Republican Calendar

The French Republican Calendar was introduced (along with

decimal time Decimal time is the representation of the time of day using units which are decimally related. This term is often used specifically to refer to the French Republican calendar time system used in #France, France from 1794 to 1800, during the Fre ...

) in 1793, and was similar to the ancient Egyptian calendar. It consisted of twelve months, each divided into three ''décades'' of ten days, with five or six intercalary days called '' sansculottides''. The calendar was abolished by

Napoleon Napoleon Bonaparte (born Napoleone di Buonaparte; 15 August 1769 – 5 May 1821), later known by his regnal name Napoleon I, was a French general and statesman who rose to prominence during the French Revolution and led Military career ...

on January 1, 1806.

Proposals

The modern

Gregorian calendar The Gregorian calendar is the calendar used in most parts of the world. It went into effect in October 1582 following the papal bull issued by Pope Gregory XIII, which introduced it as a modification of, and replacement for, the Julian cale ...

does not use decimal units of time; however, several proposed calendar systems do. None of these have achieved widespread use.

References

{{calendars Specific calendars