Spectrum Explorer

Click a region of the electromagnetic spectrum to explore its properties and uses

Radio> 1 m
Micro‑wave1 mm – 1 m
Infrared700 nm – 1 mm
Visible400 – 700 nm
UV10 – 400 nm
X-ray0.01 – 10 nm
Gamma< 0.01 nm

Radio Waves

Wavelength
> 1 metre
Frequency
< 300 MHz
Energy
Lowest
Speed (in vacuum)
3.0 × 10⁸ m/s
Radio broadcastsTV signalsMobile phones Wi-FiGPSRadar
Radio waves have the longest wavelengths and lowest energy in the spectrum. They pass through buildings and the atmosphere easily, making them ideal for long-distance communication.

Microwaves

Wavelength
1 mm – 1 m
Frequency
300 MHz – 300 GHz
Energy
Low
Speed (in vacuum)
3.0 × 10⁸ m/s
Microwave ovensSatellite communication Mobile phone networksWeather radar
Microwaves are absorbed by water molecules, which is how microwave ovens heat food. Shorter microwaves are used for high-bandwidth communication like 5G and satellite links.

Infrared

Wavelength
700 nm – 1 mm
Frequency
300 GHz – 430 THz
Energy
Low–moderate
Speed (in vacuum)
3.0 × 10⁸ m/s
Thermal imagingRemote controls Night visionHeating lamps
Infrared is emitted by all warm objects. You cannot see it, but you can feel it as heat. Snakes and some insects have sensors that detect infrared, helping them hunt in darkness.

Visible Light

Wavelength
400 – 700 nm
Frequency
430 – 750 THz
Energy
Moderate
Speed (in vacuum)
3.0 × 10⁸ m/s
VisionPhotography Fibre optic communicationPhotosynthesis
Visible light is the only part of the spectrum humans can see. Red has the longest wavelength (lowest energy) and violet has the shortest (highest energy). All colours travel at the same speed in a vacuum.

Ultraviolet (UV)

Wavelength
10 – 400 nm
Frequency
750 THz – 30 PHz
Energy
High
Speed (in vacuum)
3.0 × 10⁸ m/s
SterilisationForensic detection Vitamin D productionSunburn / skin cancer
The Sun emits UV radiation that is mostly absorbed by the ozone layer. What reaches the surface helps your skin make vitamin D, but too much causes sunburn and DNA damage. Always wear sunscreen!

X-rays

Wavelength
0.01 – 10 nm
Frequency
30 PHz – 30 EHz
Energy
Very high
Speed (in vacuum)
3.0 × 10⁸ m/s
Medical imagingAirport security Material inspectionCell damage
X-rays pass through soft tissue but are absorbed by bone and metal. This makes them invaluable for medical imaging and security scanning. High exposure is dangerous, which is why lead shields are used.

Gamma Rays

Wavelength
< 0.01 nm
Frequency
> 30 EHz
Energy
Highest
Speed (in vacuum)
3.0 × 10⁸ m/s
Cancer treatment (radiotherapy)Sterilising medical equipment Food preservationSevere cell damage
Gamma rays have the shortest wavelength and highest energy. They are produced by nuclear reactions and can penetrate most materials. While dangerous in high doses, they are also used to kill cancer cells in targeted radiotherapy.
Remember: All electromagnetic waves travel at the same speed in a vacuum — approximately 300 000 km/s. The only differences between them are wavelength and frequency, which determine their energy and how they interact with matter.