Hours to Decades (h to dec)
1 hour equals 0.00001140794586 decades (rounded).
How to convert hours to decades
To convert hours to decades, multiply the number of hours by 0.00001140794586. The factor is rounded to 10 significant digits. To go the other way, multiply decades by 87,658.2.
decades = hours × 0.00001140794586
Example: 10 hours = 0.0001140794586 decades.
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)
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
Decade (dec)
Ten years.
Greek dekas, a group of ten, gave English decade, and the Latin equivalent decennium survives in words like decennial. The idea of naming whole decades is newer. The convention of grouping years by their tens digit, so that 1960 to 1969 is the 1960s, became common in the late 19th century, and the 20th century then produced a gallery of nicknames such as the Roaring Twenties and the Swinging Sixties.
A decade is ten years, which on this site means ten average Gregorian years. The two counting styles can disagree, in the same way as with centuries: since the AD calendar has no year zero, a strict reading makes the first decade run from year 1 to year 10. A 2019 YouGov poll of 13,582 US adults found 64 percent expected the next decade to be 2020 to 2029, 17 percent said 2021 to 2030, and 19 percent did not know. Most people prefer the zero-to-nine version.
1 decade = 315,569,520 seconds (exactly).
Sources: Wikipedia: Decade; Wikipedia: Year zero
Related conversions
- Decades to hours (reverse)
- Hours to seconds
- Hours to minutes
- Hours to days
- Hours to weeks
- Hours to months
- Hours to years
- Hours to milliseconds
- Hours to microseconds
- Hours to nanoseconds
- Hours to centuries
- Hours to millennia
- Hours to picoseconds
- Seconds to decades
- Minutes to decades
- Days to decades
- Weeks to decades
- Months to decades
- Years to decades
- Milliseconds to decades
- Microseconds to decades
- Nanoseconds to decades
- Centuries to decades
- Millennia to decades
See all time units.