Quick example
Convert 60 Hz to RPM
Hertz counts cycles per second, while RPM counts revolutions per minute. Multiplying 60 cycles per second by 60 seconds per minute gives 3,600 revolutions per minute.
Quick reference
Common frequency conversions
| Starting frequency | Equivalent |
|---|---|
| 1 kHz | 1,000 Hz |
| 1 MHz | 1,000 kHz |
| 1 GHz | 1,000 MHz |
| 1 Hz | 60 cpm |
| 1 Hz | 60 RPM |
| 1 Hz | 2π rad/s |
| 1,800 RPM | 30 Hz |
| 1 rad/s | 0.1591549431 Hz |
Unit definitions
Cycles, rotations, and angular frequency
Hertz and SI prefixes
One hertz is one cycle per second. Kilohertz, megahertz, and gigahertz scale by powers of 1,000.
Cycles per minute
Cycles per minute uses the same cycle count as hertz but a 60-second time base.
RPM
Revolutions per minute describes rotational frequency. It matches cycles per minute when one revolution is one cycle.
Radians per second
Angular frequency uses radians. One complete cycle is 2π radians, so 1 Hz equals 2π rad/s.
Frequency versus direction
RPM here is a rate, not a rotation direction
This converter treats RPM and angular frequency as nonnegative rates. Clockwise and counterclockwise signs belong to an application-specific angular-velocity convention. Frequency alone does not encode that direction.
Common questions
Frequency conversion FAQ
How many RPM are in one hertz?
One hertz equals 60 RPM when each revolution is one cycle.
How do I convert RPM to hertz?
Divide RPM by 60. For example, 1,800 RPM equals 30 Hz.
How many radians per second are in one hertz?
One hertz equals exactly 2π rad/s, approximately 6.28318530718 rad/s.
Are RPM and cycles per minute the same?
They are numerically equal when one complete revolution represents one cycle.
Can frequency be negative?
Ordinary frequency is nonnegative. Directional rotation needs a separate sign convention.