How are radio frequency bands defined?

The ITU divides the radio spectrum into bands by decade of frequency. Each band spans a factor of ten, for example VHF from 30 to 300 MHz and UHF from 300 MHz to 3 GHz. The bands are named by abbreviation, from ELF (extremely low frequency) up to EHF (extremely high frequency).

How do I convert frequency to wavelength?

Wavelength equals the speed of light divided by frequency. The speed of light is about 299,792,458 metres per second. So a 100 MHz FM signal has a wavelength of roughly 3 metres, and a 2.4 GHz Wi-Fi signal about 12.5 centimetres.

What is each band used for?

VLF and LF carry navigation and time signals; MF handles AM radio; HF covers shortwave and amateur radio; VHF runs FM radio and TV; UHF carries mobile phones, Wi-Fi, and GPS; SHF and EHF handle satellite, radar, and 5G millimetre-wave links.

Why do lower frequencies travel further?

Lower-frequency, longer-wavelength signals diffract around obstacles and the curve of the Earth, and HF bands can reflect off the ionosphere for global propagation. Higher frequencies travel in straighter lines, carry more data, but are blocked more easily by terrain, buildings, and rain.

What is the relationship between wavelength and antenna size?

Efficient antennas are sized in proportion to wavelength, often a quarter or half of it. Long-wavelength VLF signals need enormous antennas, while short-wavelength microwave links use small dishes and patch antennas, which is why higher bands suit compact devices.

What is the Radio Frequency Band Reference?

A reference of the ITU radio frequency bands from ELF through EHF, with each band's frequency range, wavelength range, and typical applications. Enter any frequency to find which band it falls in and its exact wavelength. Runs in your browser. It runs free in your browser on Gera Tools, with nothing uploaded.

Radio Frequency Band Reference

Name: Radio Frequency Band Reference
Creator: Gera Tools
License: https://creativecommons.org/licenses/by/4.0/

The radio spectrum is divided by the ITU into bands, each spanning a factor of ten in frequency and named with a familiar abbreviation — VHF, UHF, SHF, and so on. This reference lists every band with its frequency range, wavelength range, and the services that typically use it, and converts any frequency you enter into its band and exact wavelength.

How it works

Frequency and wavelength are inversely related through the speed of light:

λ = c / f
c = 299,792,458 m/s   (speed of light in vacuum)

So wavelength in metres equals the speed of light divided by frequency in hertz. The ITU bands each cover one decade of frequency:

VLF  3–30 kHz      LF   30–300 kHz     MF  300 kHz–3 MHz
HF   3–30 MHz      VHF  30–300 MHz     UHF 300 MHz–3 GHz
SHF  3–30 GHz      EHF  30–300 GHz

(ELF and SLF/ULF cover everything below 3 kHz.) The tool finds which decade your frequency falls in and reports the band plus the computed wavelength.

Why band matters

Lower bands (VLF–HF) have long wavelengths, diffract around obstacles, and travel far — used for navigation, time, AM, and shortwave.
Higher bands (UHF–EHF) have short wavelengths, carry more data, and need line of sight — used for Wi-Fi, GPS, satellite, radar, and 5G.

For example, a 2.4 GHz Wi-Fi signal sits in the UHF band with a wavelength of about 12.5 cm, while a 100 MHz FM station is in VHF at about 3 m.

Familiar frequencies and their bands

Seeing well-known frequencies placed in their bands makes the system concrete:

Frequency	Band	Application
16.4 kHz	VLF	NATO’s communications to submarines
198 kHz	LF	BBC Radio 4 long wave (UK)
540–1600 kHz	MF	AM broadcast radio
3.5–30 MHz	HF	Shortwave radio, amateur radio
87.5–108 MHz	VHF	FM broadcast radio
156.8 MHz	VHF	Maritime distress (Channel 16)
470–862 MHz	UHF	Digital television broadcast
1227.6 MHz	UHF	GPS L2 signal
1575.42 MHz	UHF	GPS L1 signal
2.4 GHz	UHF	Wi-Fi 802.11b/g/n, Bluetooth, microwave ovens
5.8 GHz	SHF	Wi-Fi 802.11a/n/ac (5 GHz band)
24 GHz	SHF	Automotive radar, some 5G links
60 GHz	EHF	WiGig (802.11ad), 5G mmWave

Wavelength and antenna sizing

Efficient antenna design is tied to wavelength. A half-wave dipole antenna is sized to half the wavelength of the target frequency, and a quarter-wave monopole to one-quarter. This relationship explains why:

AM radio stations need tall mast antennas hundreds of metres high — their wavelengths are hundreds of metres.
Mobile phones can carry multiple antennas internally — at 2.4 GHz, the wavelength is about 12.5 cm, so a quarter-wave element is just over 3 cm.
Satellite dishes at SHF frequencies are the size they are — the dish must be many wavelengths across to focus the signal effectively.

Propagation differences between bands

Different bands propagate by different mechanisms, which determines their range and best applications:

Ground wave (VLF/LF/MF) — the signal follows the curvature of the Earth, allowing AM radio and maritime communications to reach hundreds of kilometres without a direct line of sight.

Ionospheric skip (HF) — signals bounce between the ionosphere and the Earth’s surface, enabling shortwave radio to reach thousands of kilometres globally, making HF the primary band for long-distance amateur radio and some emergency communications.

Line of sight (VHF and above) — the signal travels in a straight line and does not bend around the horizon. Range is limited to the visual horizon plus a small margin from diffraction. This is the propagation mode for FM radio, television, mobile phones, Wi-Fi, and satellite links.