Easy Unit Conversion

Day, Time

Day, symbol d, is a unit of time, commonly defined as an interval equal to 24 hours. It also can mean portion of the full day during which a location is illuminated by the light of the sun, also known as daytime. The period of time measured from local noon to the following local noon is called a solar day.

In 1967, the second was redefined in terms of the wavelength of light, and it became the SI base unit of time. The unit of measurement for time called "day", redefined in 1967 as 86400 SI seconds and symbolized d, is not an SI unit, but it is accepted for use with SI. A civil day is usually also 86400 seconds, plus or minus a possible leap second in Coordinated Universal Time UTC, and, in some locations, occasionally plus or minus an hour when changing from or to daylight saving time.

List of all Day to other time units individual converters.
Convert  Day

Metric, SI

Yoctosecond ys 8640000000×1019
Zeptosecond zs 8640000000×1016
Attosecond as 8640000000×1013
Femtosecond fs 8640000000×1010
Picosecond ps 8640000000×107
Nanosecond ns 8640000000×104
Microsecond µs 8640000000×101
Millisecond ms 86400000
Centisecond cs 8640000
Decisecond ds 864000
Second s 86400
Decasecond das 8640
Hectosecond hs 864
Kilosecond ks 86.4
Megasecond Ms 0.0864
Gigasecond Gs 0.0001
Terasecond Ts 8.64×10-8
Petasecond Ps 8.64×10-11
Exasecond Es 8.64×10-14
Zettasecond Zs 8.64×10-17
Yottasecond Ys 8.64×10-20

Common units

Minute min 1440
Hour h 24
Week 0.1429
Fortnight 0.0714
Month 0.0329
Year y 0.0027
Decade 0.0003
Century 2.7397×10-5
Millennium 2.7397×10-6

Sidereal time

Sidereal second 86636.5559
Sidereal minute 1443.9426
Sidereal hour 24.0657
Sidereal day 1.0027
Sidereal year 0.0027


Shake 8640000000×103
Synodic month 0.0339
Leap year 0.0027
Julian year 0.0027
Tropical year 0.0027
Septennial 0.0004
Octennial 0.0003
Novennial 0.0003
Quindecennial 0.0002
Quinquennial 0.0005

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