Wavelength to Energy Calculator: Photon Energy (E=hc/λ)

Wavelength → Energy Calculator

E = h·c/λ • Photon energy • Unit conversion • Ajax loading

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🌊 Wave speed (c in medium)

Custom c must be > 0. Presets approximate typical conditions.

📦 Primary output unit

We always compute all 3; this controls the main highlighted value.

Quick summary

Enter wavelength λ to compute photon energy.

📏 Wavelength (λ)

λ must be > 0.

🧪 Constants used

h = 6.62607015×10⁻³⁴ J·s • e = 1.602176634×10⁻¹⁹ C • N_A = 6.02214076×10²³ mol⁻¹

Primary energy

— —

Energy (J per photon)

— J

Energy (eV per photon)

— eV

Energy (kJ/mol photons)

— kJ/mol

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