Hours to Centuries (h to c)

1 hour equals 0.000001140794586 centuries (rounded).

1 hour = 0.000001140794586 centuries

How to convert hours to centuries

To convert hours to centuries, multiply the number of hours by 0.000001140794586. The factor is rounded to 10 significant digits. To go the other way, multiply centuries by 876,582.

centuries = hours × 0.000001140794586

Example: 10 hours = 0.00001140794586 centuries.

Months and years are not constant. This site uses the average Gregorian year of 365.2425 days, so one 'year' converts to 365.2425 days, not 365; use 'common year' for exactly 365 days.

About these units

Hour (h)

Metric (SI)Current unit

60 minutes or 3,600 seconds, one twenty-fourth of a mean solar day.

Egyptian astronomers gave us the twelve. Coffin lids from about 2150 BC show the night divided into exactly 12 intervals, tied to the rising of star groups called decans, and the day was later split into 12 hours with sundials. These were seasonal hours, a twelfth of the daylight, so a summer hour was longer than a winter one. The word itself comes from Greek hora, originally any span of time, through Latin and Old French into English in the 13th century.

Equal hours of 1/24 of a day were probably first proposed by Hipparchus, and mechanical clocks made them the practical choice, since a clock showing seasonal hours had to be readjusted every morning and evening. Today the hour is exactly 3,600 seconds and is a non-SI unit accepted for use with the SI. Civil time still bends it a little: UTC hours have lasted 3,601 seconds 27 times since 1972 to keep clocks within 0.9 seconds of the Earth's rotation. In practice we use it for working shifts, travel times and electricity bills measured in kilowatt-hours.

1 hour = 3,600 seconds (exactly).

Sources: Wikipedia: Hour; BIPM: SI Brochure, 9th edition

Century (c)

CalendarCurrent unit

One hundred years.

From Latin centum, a hundred, century has meant a hundred of many things. For time it became popular as a way to speak about a span longer than a lifetime can easily contain, and some languages organise history around it: Italian uses terms like Quattrocento for the 15th century, and Swedish writes 1900-talet for the years 1900 to 1999. Whether such a century starts at year 00 or year 01 is an old argument.

A century is 100 years, which here means 100 average Gregorian years. The strict view counts from year 1, because the AD calendar has no year zero, so the 1st century AD ran from AD 1 to AD 100 and the 21st century covers 2001 to 2100. The popular view groups years by their hundreds digit, making the 20th century 1900 to 1999. The Gregorian calendar itself treats century years specially, since 1700, 1800 and 1900 were not leap years while 1600 and 2000 were.

1 century = 3,155,695,200 seconds (exactly).

Sources: Wikipedia: Century; Wikipedia: Gregorian calendar

Related conversions

See all time units.