What is the relationship?

c = f × λ (speed of light = frequency × wavelength). For EM waves, c ≈ 3 × 10⁸ m/s.

What is photon energy?

E = hf where h is Planck's constant. Higher frequency = higher energy.

Wavelengths from ~380nm (violet) to ~700nm (red), frequencies ~430-790 THz.

Last Updated: April 13, 2026

Free wavelength and frequency calculator. Convert between wavelength, frequency, and energy for EM waves.

Frequency (Hz)

Wavelength (m, 0 = auto)

Wavelength

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Frequency

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Photon Energy

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Band

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