Energy to Wavelength Calculator
Convert photon energy to its wavelength.
Convert a photon's energy into the wavelength of light it corresponds to.
The math behind it
λ = h·c ÷ E. A handy shortcut: λ(nm) ≈ 1240 ÷ E(eV).
Worked example
2.5 eV → about 496 nm (blue-green).
FAQ
What's the 1240 rule?
λ in nm ≈ 1240 divided by energy in eV — a quick photon conversion.