Frequency Converter
Convert any frequency — radio, audio, mechanical or angular. Hz, mHz, μHz, kHz, MHz, GHz, THz, rpm and rad/s.
1 Megahertz (MHz) =
0
Converted via 1000000 Hz per mhz and 1000000000 Hz per ghz. 1 kHz = 10³ Hz, 1 MHz = 10⁶ Hz, 1 GHz = 10⁹ Hz, 1 THz = 10¹² Hz (exact SI prefixes). 1 rpm = 1/60 Hz exactly; 1 rad/s = 1/(2π) Hz exactly.
How to use this calculator
Enter a value, choose your starting unit from "From", then pick the target unit in "To". Results update instantly. Use Hz for audio and low-frequency signals, kHz for AM radio and ultrasound, MHz for FM radio and CPU clocks of the 1990s, GHz for Wi-Fi, mobile networks and modern CPUs, THz for optical and infrared light, rpm for engines and motors, and rad/s for angular velocity in physics.
How the calculation works
Every unit converts via a single intermediate value in hertz (1 Hz = 1 cycle per second, the SI derived unit of frequency). SI prefix factors are exact decimal powers: 1 kHz = 10³ Hz, 1 MHz = 10⁶ Hz, 1 GHz = 10⁹ Hz, 1 THz = 10¹² Hz (BIPM SI Brochure, 9th ed.). Mechanical and angular units: 1 rpm = 1/60 Hz exactly (one revolution per 60 seconds); 1 rad/s = 1/(2π) Hz exactly, since one full cycle equals 2π radians.
Worked example
2.4 GHz Wi-Fi → megahertz: 2.4 × 10⁹ ÷ 10⁶ = 2400 MHz. The same 2.4 GHz channel in hertz is 2 400 000 000 Hz, and as a wavelength it gives c ÷ f = 299 792 458 ÷ 2.4×10⁹ ≈ 0.125 m, the well-known ~12.5 cm 2.4 GHz wavelength.
Frequently asked questions
What is one hertz?
One hertz (Hz) is one cycle per second — the SI derived unit of frequency, named after Heinrich Hertz, who first demonstrated electromagnetic waves in 1887. A 1 Hz signal completes one full oscillation every second. Human hearing covers roughly 20 Hz to 20 000 Hz (20 kHz). Mains electricity is 50 Hz across most of the world and 60 Hz in North America. Hz is defined as s⁻¹ in the SI base units.
How many Hz is 1 MHz, 1 GHz and 1 THz?
1 kHz = 1 000 Hz (10³). 1 MHz = 1 000 000 Hz (10⁶). 1 GHz = 1 000 000 000 Hz (10⁹). 1 THz = 1 000 000 000 000 Hz (10¹²). The SI prefixes are exact decimal powers, so 2.4 GHz is exactly 2 400 000 000 Hz or 2 400 MHz, and a 5 GHz Wi-Fi band is exactly 5 000 MHz.
How do I convert rpm to Hz?
Divide rpm by 60. One revolution per minute equals 1/60 of a revolution per second, which is 1/60 Hz. So 3000 rpm = 50 Hz, 6000 rpm = 100 Hz, and 60 000 rpm (an aggressive turbocharger) = 1000 Hz = 1 kHz. To go the other way, multiply Hz by 60: a 50 Hz mains-frequency synchronous motor at 2 poles spins at 50 × 60 = 3000 rpm (at 4 poles, 1500 rpm — the pole count halves the speed).
How do I convert rad/s to Hz?
Divide rad/s by 2π. One full cycle is 2π radians, so 1 rad/s = 1 / (2π) ≈ 0.159 155 Hz. For example, an angular velocity of 314.159 rad/s = 314.159 / (2π) = 50 Hz, which is the mains frequency in the UK. To go the other way, multiply Hz by 2π: a 50 Hz mains signal has angular frequency ω = 2π × 50 ≈ 314.16 rad/s.
How is frequency related to wavelength?
For any wave, c = f × λ, where c is the wave speed, f is frequency in Hz, and λ is wavelength in metres. For electromagnetic waves in vacuum, c = 299 792 458 m/s exactly. So 2.4 GHz Wi-Fi has wavelength 299 792 458 / 2.4×10⁹ ≈ 0.125 m (12.5 cm). For sound in air at 20 °C (c ≈ 343 m/s), middle A (440 Hz) has wavelength 343 / 440 ≈ 0.78 m. Higher frequency = shorter wavelength.
Why is mains electricity 50 Hz in Europe and 60 Hz in the US?
Historical accident. Late-19th-century US electrification, led by Westinghouse and Tesla, settled on 60 Hz partly because it suited the early AC motors and arc lighting that drove demand. AEG in Germany standardised on 50 Hz around 1891 for similar engineering reasons. Both grew into incompatible grids before any international standard could form. 60 Hz lets motors run slightly faster and transformers be slightly smaller; 50 Hz has marginally better long-distance transmission. Both work equally well — they are just incompatible, which is why your travel hair-dryer hates 50 Hz visits.