Centuries to Days (c to d)
1 century equals 36,524.25 days exactly.
How to convert centuries to days
To convert centuries to days, multiply the number of centuries by 36,524.25. This factor is exact. To go the other way, multiply days by 0.00002737907007 (rounded).
days = centuries × 36,524.25
Example: 10 centuries = 365,242.5 days.
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
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
Day (d)
24 hours or 86,400 seconds. The mean solar day; the actual rotation of the Earth is about 4 minutes shorter (see sidereal day).
Old English dæg is the root of our day, with close cousins in German Tag, Dutch dag and Icelandic dagur, all descending from Proto-Germanic dagaz. It is the oldest unit here, because the cycle of light and dark needs no instrument. Yet the day we count is a constructed average: the actual interval from one noon to the next varies through the year by up to about 7.9 seconds, because Earth's orbit is elliptical and its axis is tilted.
Astronomers smooth this out with a fictitious mean Sun, giving the mean solar day, and the day in the SI sense is fixed at exactly 86,400 seconds. Reality has drifted slightly: the mean solar day has recently averaged about 86,400.002 seconds, and tidal drag from the Moon is lengthening it by about 2 milliseconds per century. That is why 27 leap seconds were added to UTC between 1972 and 2022. One rotation measured against the distant stars is shorter, about 23 hours 56 minutes 4.09 seconds, and a year contains one more of these sidereal days than solar days.
1 day = 86,400 seconds (exactly).
Sources: Wikipedia: Day; BIPM: SI Brochure, 9th edition
Related conversions
- Days to centuries (reverse)
- Centuries to seconds
- Centuries to minutes
- Centuries to hours
- Centuries to weeks
- Centuries to months
- Centuries to years
- Centuries to milliseconds
- Centuries to microseconds
- Centuries to nanoseconds
- Centuries to decades
- Centuries to millennia
- Seconds to days
- Minutes to days
- Hours to days
- Weeks to days
- Months to days
- Years to days
- Milliseconds to days
- Microseconds to days
- Nanoseconds to days
- Decades to days
- Millennia to days
- Picoseconds to days
See all time units.