Convert between Second and other Time units.

## Second

What is the second?

The second is an important unit of time. It is the main unit of time in the SI system of units. It can be defined as the time it takes an electromagnetic field to propagate through 3 x 10 5 km of vacuum.

One solar day has 86,400 seconds. There are 60 second per minute.

Second is not small and specific enough to be used by scientists and engineers so smaller units were derived such as:

• One millisecond which equals 10 -3 s.
• One microsecond which equals 10 -6 s.
• One nanosecond which equals 10 -9 s.
• One picosecond which equals 10 -12 s.
Second to Minute | Second to Hour | Second to Week | Second to Month | Second to Year |
Attosecond
Century
Day
Day (sidereal)
Femtosecond
Fortnight
Hour
Hour (sidereal)
Microsecond
Millennium
Millisecond
Minute
Minute (sidereal)
Month
Month (synodic)
Nanosecond
Novennial
Octennial
Picosecond
Planck time
Quindecennial
Quinquennial
Second (sidereal)
Septennial
Shake
Week
Year
Year (Julian)
Year (leap)
Year (sidereal)
Year (tropical)