Wavelength & Frequency Calculator

About this calculator

Every electromagnetic wave — radio, microwave, visible light, X-rays — obeys the fundamental relationship c = f · λ, where c is the speed of light in a vacuum (≈299,792,458 m/s), f is the wave's frequency, and λ is its wavelength. Because c is constant, frequency and wavelength are inversely proportional: doubling the frequency halves the wavelength, and vice versa. This calculator converts freely between the two, solving f = c/λ or λ = c/f.

Radio and RF engineers use this relationship to design antennas (whose optimal length is typically a fraction of the signal's wavelength), broadcast engineers use it to convert station frequencies to wavelengths, and physics and optics students use it to move between the frequency and wavelength descriptions of light, since spectroscopy, color science and quantum energy calculations (via E = hf) often require converting one to the other.