How to use the frequency converter
- 1 Type the value you want to convert.
- 2 Choose the unit to convert from and the unit to convert to.
- 3 Press ⇄ to swap the two units.
- 4 Read the result, and see the same frequency in every other unit in the table below.
Frequency and rotation
Hertz counts cycles per second; rpm counts turns per minute, so divide rpm by 60 for hertz. For time per cycle, take 1 divided by the frequency: 50 Hz gives 0.02 seconds, which you can convert with the Time Converter.
- Higher radio frequencies carry more data but travel less far.
- Mains frequency is 50 Hz or 60 Hz depending on the country.
- Fan and motor nameplates give rpm at the rated supply frequency.
Features
Five units
Hz, kHz, MHz, GHz and rpm.
Motors and fans
rpm to Hz for motors, fans and drives.
Electronics
MHz and GHz for radio, Wi-Fi and processors.
When to use it
Radio and Wi-Fi
FM stations broadcast around 88 to 108 MHz; Wi-Fi uses 2.4 GHz and 5 GHz bands.
Computers
A 3.5 GHz processor runs at 3,500 MHz.
Motors and fans
A motor at 1,500 rpm turns 25 times a second, 25 Hz. On a 50 Hz supply, a four-pole motor runs just below 1,500 rpm.
Audio
Human hearing is roughly 20 Hz to 20 kHz; CD audio samples at 44.1 kHz.
Related Unit tasks
Frequently asked questions
How do I convert rpm to Hz?
Divide by 60. 3,000 rpm is 50 Hz.
How do I convert Hz to rpm?
Multiply by 60. 25 Hz is 1,500 rpm.
How many kHz in a MHz?
1,000 kHz.
What is the mains frequency?
50 Hz in Pakistan, India, the UK, Europe and Australia, and 60 Hz in the US, Canada and parts of South America.
What does GHz mean for a processor?
Billions of clock cycles per second. A higher number is faster within the same processor family, but design matters too.
What is a hertz?
One cycle per second, named after the physicist Heinrich Hertz.
How do frequency and wavelength relate?
Wavelength equals the speed of light divided by frequency. A 100 MHz radio wave is about 3 metres long.
What frequency is AM radio?
Medium wave AM uses about 530 to 1,700 kHz.
Is rpm the same as Hz?
Both measure how often something repeats, but rpm counts per minute and Hz per second, so they differ by 60.
Are the results exact?
Yes; these units differ by exact powers of ten or by 60.
Why does my fan speed say rpm?
Motors and fans are rated by how many full turns they make each minute. Converting to hertz shows how many turns happen each second, which helps when matching motors to drives and supplies.
What do kilohertz mean for audio quality?
The sample rate of digital audio, such as forty-four point one or forty-eight kilohertz, sets the highest sound frequency that can be recorded, which is about half the sample rate.
Why do Wi-Fi routers offer two bands?
The lower band reaches further through walls but is more crowded and slower, while the higher band is faster at short range. Most routers let devices switch between them automatically.
What is the frequency of a musical note?
The note A above middle C is tuned to four hundred and forty hertz in most modern music. Each octave higher doubles the frequency, and each octave lower halves it.
Can a 60 Hz appliance work on 50 Hz?
Many electronic devices with switch-mode chargers handle both. Motors and clocks designed for sixty hertz can run slower or hotter on fifty, so check the label before using them.
Built and reviewed by Hamza Farooq, founder and lead developer
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