Frequency / Wavelength / Energy Converter

Enter any one quantity and all others update instantly. Covers the full electromagnetic spectrum from ELF radio waves to X-rays, including the Larmor frequencies used in MRI and NMR spectroscopy.

Equations & Parameters ▸

f	Frequency (Hz, kHz, MHz, GHz, THz).
λ	Free-space wavelength = c/f.
T	Period = 1/f.
E	Photon energy in eV = hf/e. Useful for quantum/NMR applications.
B₀	Static B₀ field for ¹H MRI at this Larmor frequency. f = 42.577 MHz/T × B₀.

Physical constants used

c	Speed of light = 2.998×10⁸ m/s
µ₀	Permeability of free space = 4π×10⁻⁷ H/m ≈ 1.2566×10⁻⁶ H/m
ε₀	Permittivity of free space = 8.854×10⁻¹² F/m
k_B	Boltzmann constant = 1.381×10⁻²³ J/K
h	Planck constant = 6.626×10⁻³⁴ J·s
¹H gyromagnetic ratio	γ/2π = 42.577 MHz/T

Reference: Standard relationships; see Griffiths, Introduction to Electrodynamics, §9.2

Enter any one value

Frequency, f

Wavelength, λ

free space

Period, T

Photon energy, E

hf/e

Results

Electromagnetic

Frequency, f—

Wavelength, λ—

Period, T—

Wave number, k—

Angular frequency, ω—

Quantum & MRI

Photon energy (eV)—

Photon energy (J)—

¹H B₀ field (NMR)—

Band—

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