Weeks to Decades (wk to dec)
1 week equals 0.001916534905 decades (rounded).
How to convert weeks to decades
To convert weeks to decades, multiply the number of weeks by 0.001916534905. The factor is rounded to 10 significant digits. To go the other way, multiply decades by 521.775.
decades = weeks × 0.001916534905
Example: 10 weeks = 0.01916534905 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
Week (wk)
Seven days. The seven-day week comes from the ancient Near East and is nearly universal in the modern calendar.
Nothing in the sky produces a seven-day cycle, which makes the week a human invention with a contested pedigree. Babylonians marked the 7th, 14th, 21st and 28th of the lunar month as special, but that was not a continuous cycle. A continuous seven-day cycle tied to the Sabbath is attested in Judaism by the 6th century BC at the latest, and scholars disagree on whether it was borrowed from Babylon or developed independently. The Romans later used a week named for the Sun, the Moon and the five visible planets, and in AD 321 Emperor Constantine decreed it across the empire.
A week is seven days, or 604,800 seconds, and it divides evenly into neither months nor years, which is why calendars shift against it. The ISO 8601 standard starts each week on Monday and assigns week 1 to the week containing the year's first Thursday, so some years have a week 53. Other societies used different lengths: Rome had an eight-day market cycle, and revolutionary France used a ten-day week from 1793 to 1802. The English word comes from Old English wice, meaning a turn or succession.
1 week = 604,800 seconds (exactly).
Sources: Wikipedia: Week; Wikipedia: ISO week date
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 weeks (reverse)
- Weeks to seconds
- Weeks to minutes
- Weeks to hours
- Weeks to days
- Weeks to months
- Weeks to years
- Weeks to milliseconds
- Weeks to microseconds
- Weeks to nanoseconds
- Weeks to centuries
- Weeks to millennia
- Weeks to picoseconds
- Seconds to decades
- Minutes to decades
- Hours to decades
- Days 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.