Years to Centuries (yr to c)
1 year equals 0.01 centuries exactly.
How to convert years to centuries
To convert years to centuries, multiply the number of years by 0.01. This factor is exact. To go the other way, multiply centuries by 100.
centuries = years × 0.01
Example: 10 years = 0.1 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
Year (yr)
The average Gregorian calendar year of 365.2425 days (31,556,952 seconds). A common year has 365 days and a leap year 366.
A year is the Earth's trip around the Sun, but there are several versions. The tropical year, which tracks the seasons, is about 365.2422 days. The sidereal year, measured against the stars, is about 365.2564 days, roughly 20 minutes longer, because the Earth's axis precesses. Calendars must squeeze these into whole days, which is the origin of leap years. English year descends from Old English gear, while Latin annus, the source of annual, comes from a different root.
The Gregorian calendar, introduced by Pope Gregory XIII's bull of 24 February 1582, fixed the problem of Julian drift that had moved the March equinox away from 21 March and upset the date of Easter. Ten days were skipped, so Thursday 4 October was followed by Friday 15 October. Its rule of skipping leap days in century years not divisible by 400 gives a mean year of 365.2425 days, the value this site uses for the year. Britain and its empire switched in 1752 and Russia in 1918. Scientists write the year as a, with the Julian year fixed at 31,557,600 seconds.
1 year = 31,556,952 seconds (exactly).
Sources: Wikipedia: Year; Wikipedia: Gregorian calendar
Century (c)
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
- Centuries to years (reverse)
- Years to seconds
- Years to minutes
- Years to hours
- Years to days
- Years to weeks
- Years to months
- Years to milliseconds
- Years to microseconds
- Years to nanoseconds
- Years to decades
- Years to millennia
- Years to picoseconds
- Seconds to centuries
- Minutes to centuries
- Hours to centuries
- Days to centuries
- Weeks to centuries
- Months to centuries
- Milliseconds to centuries
- Microseconds to centuries
- Nanoseconds to centuries
- Decades to centuries
- Millennia to centuries
See all time units.