The radian per second (symbol: rad·s−1 or rad/s) is the SI unit of rotational speed (angular velocity), commonly denoted by the Greek letter ω (omega). The radian per second is also the unit of angular frequency. The radian per second is defined as the change in the orientation of an object, in radians, every second.

Angular frequency ω (Ordinary) frequency ${\displaystyle \nu =\omega /{2\pi }}$
2π radians per secondexactly 1 hertz (Hz)
1 radian per secondapproximately 0.159155 Hz
1 radian per secondapproximately 57.29578 degrees per second
1 radian per secondapproximately 9.5493 revolutions per minute (rpm)
0.1047 radians per secondapproximately 1 rpm
Angular frequency ω (in radians per second), is larger than frequency ν (in cycles per second, also called Hz), by a factor of 2π, because 2π rad/s corresponds to 1 Hz.
General information
Unit systemSI derived unit
Unit ofrotational speed