Unit converter
Frequency.
Convert Hz to rpm, or pick any of the 7 units in the menus. Type in either box and the other follows. Cycles per second, plus revolutions and beats per minute. Angular velocity is a different quantity and lives on its own page.
| Hz | rpm |
|---|---|
| 1 Hz | 60 rpm |
| 2 Hz | 120 rpm |
| 3 Hz | 180 rpm |
| 4 Hz | 240 rpm |
| 5 Hz | 300 rpm |
| 10 Hz | 600 rpm |
| 15 Hz | 900 rpm |
| 20 Hz | 1200 rpm |
| 25 Hz | 1500 rpm |
| 50 Hz | 3000 rpm |
| 75 Hz | 4500 rpm |
| 100 Hz | 6000 rpm |
| 250 Hz | 15000 rpm |
| 500 Hz | 30000 rpm |
| 1000 Hz | 60000 rpm |
- Every unit in the menus is defined against Hz, so any pairing converts by the same single route.
Definitions
- The hertz is one cycle per second, the SI unit of frequency.
- Revolutions per minute is one sixtieth of a hertz. Engine and disc speeds are quoted in it.
- Frequency counts cycles per second. Angular velocity in rad/s differs by a factor of 2π and is kept in its own converter.
- Every unit in the menus is exact by definition, so the only rounding on this page is the one you choose for the display.
How it works
Every value is converted into hertz and then back out into the unit you asked for. One route covers every pairing in the menus, so an unusual combination is no less accurate than a common one, and adding a unit affects only that unit.
Both boxes are live. Whichever one you last typed in is the source, changing either menu recalculates straight away, and Swap exchanges the units and the values so the number you are reading stays where you are looking.
Display precision limits significant figures rather than decimal places, because one fixed number of decimals is useless across a range this wide. Very large and very small results switch to scientific notation with a proper superscript exponent. The editable box always holds a plain number at full working precision, so you can carry on from either side.
Common questions this answers: how many revolutions per minute in a hertz (60), how many hertz in a revolution per minute (0.0166667), and what 50 Hz is in revolutions per minute (3000 rpm).
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- No tracking
- No account
- Works offline once loaded
From the maker of Ans — a scientific calculator you can own. Same idea: a proper instrument, nothing in the way.