Wavelength ↔ Frequency Calculator
c = λ × ν. Wavelength in vacuum from frequency or vice versa. c = 3×10⁸ m/s.
Result
General calculation reads
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How to use this calculator
- Pick direction.
- Enter freq or wavelength.
- Pick medium for refractive correction.
About this calculator
Speed of light c = λ × ν (frequency). Vacuum c ≈ 3 × 10⁸ m/s. In other media, c reduces by 1/n. Visible light: 380-750 nm wavelength = 4-7.9 × 10¹⁴ Hz frequency. Photon energy E = hν = 6.626 × 10⁻³⁴ × frequency. UV is more energetic per photon (~3-100 eV) — this is why it damages DNA. Radio waves: low energy (~ 10⁻⁹ eV per photon).
Frequently asked
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