Frequency Converter
Convert a frequency between hertz, kilohertz, megahertz, gigahertz, and revolutions per minute. One rpm is 1/60 hertz. This page does not compute wavelength.
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How to convert hertz to rpm
- Enter the frequency. The default is 1 hertz.
- Keep From as Hertz and To as Revolutions per minute, or pick kHz, MHz, or GHz.
- Read rpm. Multiply hertz by 60.
- Swap units to start from rpm. Shaft speed with teeth or poles belongs on the RPM calculator.
Hertz
SI frequency (1/s)
| Hertz | 1 Hz = 1 cycle per second |
|---|---|
| RPM | 1 rpm = 1/60 Hz, one revolution per minute |
| Kilohertz | 1 kHz = 1000 Hz |
| Megahertz | 1 MHz = 1e6 Hz |
| Gigahertz | 1 GHz = 1e9 Hz |
| Wavelength | c = fλ lives on the wavelength calculator, not here |
What this frequency converter does
Frequency counts events per second. The SI unit is the hertz. Revolutions per minute treat one shaft turn as one event, so 60 rpm = 1 Hz and 1 rpm = 1/60 Hz. Radio and clock crystals use kHz, MHz, and GHz as SI prefixes on the same hertz. This form starts at hertz and targets rpm so a motor plate and a lab oscillator share one table.
Shaft speed from poles, teeth, or belt ratio belongs on the RPM calculator. Light or radio wavelength from frequency belongs on wavelength and frequency. Other dimensions sit on the unit converter.
Hertz and rpm factors
rpm = Hz × 60. Hz = rpm / 60. kHz = Hz / 1000. MHz = Hz / 1e6. GHz = Hz / 1e9. The engine stores hertz as the canonical unit. It does not assume two pulses per revolution or a gear ratio. Those jobs need the RPM calculator.
Cycles, revolutions, and waves
An AC mains of 50 Hz is 3000 rpm only if you treat each cycle as one revolution, which is the wrong model for a four-pole induction motor. This page never inserts poles. Electromagnetic wavelength is speed of light divided by frequency. Sound wavelength needs a sound speed you type on the wavelength page. Neither λ nor c is an input here.
When to convert frequency here
Turn a tachometer rpm into hertz, label a crystal in MHz as Hz, or compare GHz and MHz on the same oscillator. Leave belt math and wavelength on the science calculators.
What this page does not do
It does not compute wavelength. It does not apply pole pairs or gear teeth. It is not a spectrum analyzer. Input stays in this tab.