Seconds to Fortnights (s to fortnight)
1 second equals 8.267195767×10⁻⁷ fortnights (rounded).
How to convert seconds to fortnights
To convert seconds to fortnights, multiply the number of seconds by 8.267195767×10⁻⁷. The factor is rounded to 10 significant digits. To go the other way, multiply fortnights by 1,209,600.
fortnights = seconds × 8.267195767×10⁻⁷
Example: 10 seconds = 0.000008267195767 fortnights.
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
Second (s)
The SI base unit of time, defined by the radiation frequency of the cesium-133 atom: 9,192,631,770 cycles per second.
Our word second is a leftover of Latin. Medieval scholars divided a degree, and later the hour, into 60 parts called pars minuta prima, the first small part, and divided those again into pars minuta secunda, the second small part. NIST traces the roots further back: Babylonian and Greek astronomers split the circle into 360 degrees, and around 150 C.E. Ptolemy split each degree into 60 minutes and each minute into 60 seconds. Clocks that could show seconds appeared only in the later 16th century, and Christiaan Huygens's pendulum clock of 1656 was the first able to keep time accurately to the second.
For most of history the second was a fraction of a day, and in 1956 it was redefined as a fraction of the tropical year, a definition the SI took over in 1960. In 1967 the 13th CGPM switched to atoms: 9,192,631,770 periods of the radiation tied to a hyperfine transition of caesium-133. The 2019 SI revision restated this by fixing the caesium frequency at 9,192,631,770 hertz. NIST reports that commercial caesium clocks stay within about a three-millionth of a second per year, and experimental clocks based on other atoms are roughly ten thousand times more precise.
The second is the reference unit for time on this site.
Sources: NIST: the second and the SI redefinition; BIPM: SI Brochure, 9th edition; Wikipedia: Second
Fortnight (fortnight)
Fourteen days; short for 'fourteen nights'. Common in British English.
English inherited fortnight from Old English feowertyne niht, fourteen nights, a reminder that early Germanic peoples reckoned time by nights rather than days. It means exactly two weeks, or 14 days, which is 1,209,600 seconds. Many languages lack a single word for the span, so speakers say two weeks or fourteen days instead.
Other languages tend to count inclusively, as in Welsh pythefnos, meaning fifteen nights, matching wythnos for a week, or Spanish quincena and French quinzaine, which all point to fifteen. The Hindu calendar uses paksa for a half of a lunar month. In astronomy a lunar fortnight is half a synodic month, about 14.77 days, which is slightly longer than the calendar fortnight. Neighbouring units are the week, at half a fortnight, and the month, which holds roughly two of them.
1 fortnight = 1,209,600 seconds (exactly).
Sources: Wikipedia: Fortnight
Related conversions
- Fortnights to seconds (reverse)
- Seconds to minutes
- Seconds to hours
- Seconds to days
- Seconds to weeks
- Seconds to months
- Seconds to years
- Seconds to milliseconds
- Seconds to microseconds
- Seconds to nanoseconds
- Seconds to decades
- Seconds to centuries
- Seconds to millennia
- Minutes to fortnights
- Hours to fortnights
- Days to fortnights
- Weeks to fortnights
- Months to fortnights
- Years to fortnights
See all time units.