Wavelength ↔ Frequency
Convert between wavelength and frequency for electromagnetic waves.
Wavelength and frequency of light
Every electromagnetic wave links wavelength and frequency through the speed of light: c = λf. This converter turns one into the other, whether you are working with radio waves, visible light, or anything between.
A 500 nm wavelength (5×10⁻⁷ m), roughly green light, corresponds to a frequency of about 600 THz. The tool shows the result in base units and in friendlier ones like nanometres and terahertz.
Exact and private
It uses the defined vacuum speed of light and computes the conversion in your browser with nothing uploaded.
Frequently Asked Questions
What relationship is used?
c = λ × f, where c is the speed of light in a vacuum (299,792,458 m/s). Enter a wavelength to get frequency, or a frequency to get wavelength.
Does this apply to all light?
It uses the vacuum speed of light, which is accurate for radio, microwave, infrared, visible, and beyond. In a medium the speed and wavelength are slightly lower.
What units does it accept?
Wavelength in metres and frequency in hertz; the tool also shows convenient units like nm and THz for visible light.
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