Frequency Converter — hertz, kHz, MHz, GHz & rpm

How it works

Frequency counts how often something repeats each second. The SI unit is the hertz (Hz) — one cycle per second. The common units step by powers of a thousand (NIST SP 811):

• 1 kilohertz (kHz) = 1,000 Hz, 1 megahertz (MHz) = 1,000,000 Hz, and 1 gigahertz (GHz) = 1,000,000,000 Hz — the scale of radio, audio and processor clock speeds.
• 1 rpm (revolution per minute) = 1/60 Hz, because a minute has 60 seconds — so 60 rpm is exactly 1 Hz.

The calculator converts your value to hertz and then to the unit you want, so any pairing works the same way.

Worked example

Converting 1 gigahertz to megahertz: 1 GHz = 1,000 MHz. And 60 rpm = 1 Hz, while 1 megahertz = 1,000 kHz.

Frequently asked questions

How many megahertz are in a gigahertz?

Exactly 1,000. Each step up — kilo, mega, giga — multiplies by 1,000, so 2.4 GHz (a common Wi-Fi band) is 2,400 MHz.

How do I convert rpm to hertz?

Divide rpm by 60, since one hertz is one cycle per second and a minute has 60 seconds. So 3,000 rpm ÷ 60 = 50 Hz.

What is a hertz?

The SI unit of frequency — one cycle, or repetition, per second. A 50 Hz mains supply alternates 50 times each second.

How are Wi-Fi and radio frequencies measured?

In megahertz and gigahertz. FM radio is around 100 MHz, and Wi-Fi uses 2.4 GHz and 5 GHz bands — billions of cycles per second.

Is rpm a frequency?

Yes — revolutions per minute counts repetitions over time, just per minute instead of per second. Divide by 60 to express it in hertz.

Do processor clock speeds use these units?

Yes. A 3.2 GHz processor completes about 3.2 billion clock cycles per second, which is 3,200 MHz.