Convert RPM to Hertz
RPM to hertz is the conversion you need when you have a rotation speed — an engine, a motor, a hard drive, a turntable — and want it as a plain frequency in cycles per second. The clean way to do it is to divide the RPM by 60, since 60 revolutions per minute is exactly 1 hertz. Written as a single multiplier, 1 RPM is about 0.0166667 Hz, a repeating decimal that has to be rounded.
Revolutions per minute to Hertz conversion table
| Revolutions per minute (rpm) | Hertz (Hz) |
|---|---|
| 1 | 0.016667 |
| 2 | 0.033333 |
| 3 | 0.05 |
| 5 | 0.083333 |
| 10 | 0.166667 |
| 20 | 0.333333 |
| 50 | 0.833333 |
| 100 | 1.666667 |
| 500 | 8.333333 |
| 1,000 | 16.666667 |
The formula
To convert RPM to hertz, divide the revolutions per minute by 60:
hertz = RPM ÷ 60
Written as a multiplier instead, 1 RPM is about 0.0166667 Hz, but the division by 60 is the clean way to do it.
A worked example
Say a motor spins at 3000 RPM and you want that as a frequency in hertz:
3000 ÷ 60 = 50 Hz
So 3000 RPM is exactly 50 Hz.
Why it's an approximation
The clean part is the division: RPM ÷ 60. Because there are exactly 60 seconds in a minute, dividing by 60 turns revolutions per minute into revolutions per second, and round RPM values like 3000 give an exact answer — 50 Hz on the nose. The approximation only creeps in when you write the rule as a single multiply-factor. One RPM is 1/60 of a hertz, and 1/60 as a decimal is 0.016666… repeating without end, so the multiplier 0.0166667 is rounded. Stick to dividing by 60 and you keep the exact result.
When you'll use it
Reading engine or motor speeds as a frequency, checking hard-drive or turntable rotation rates, and comparing rotation speed against anything else already measured in hertz.
Frequently asked questions
How do I convert RPM to hertz?
Divide the RPM by 60. There are 60 seconds in a minute, so revolutions per minute divided by 60 gives you revolutions per second, which is hertz. For example, 3000 RPM ÷ 60 = 50 Hz.
How many hertz is 3000 RPM?
Exactly 50 Hz. Since 60 RPM is 1 Hz, dividing 3000 by 60 lands on a clean 50 — no rounding needed for round RPM values like this one.
Is 1 RPM equal to 0.0166667 hertz?
Roughly. One RPM is 1/60 of a hertz, and 1/60 as a decimal is 0.016666… repeating forever, so 0.0166667 is a rounded figure. The exact relationship is the clean division: RPM ÷ 60.