Photon Energy Calculator

Calculate the energy of photons based on wavelength or frequency

About Photon Energy

The energy of a photon can be calculated using Planck’s equation: E = h × ν or alternatively E = (h × c) / λ, where:

  • E is the photon energy
  • h is Planck’s constant (6.626 × 10⁻³⁴ J·s)
  • ν (nu) is the photon frequency
  • λ (lambda) is the photon wavelength
  • c is the speed of light (3 × 10⁸ m/s)

Frequently Asked Questions

Photon energy is the energy carried by a single photon, which is directly proportional to its electromagnetic frequency and inversely proportional to its wavelength.

You can calculate photon energy from wavelength using the equation: E = (h × c) / λ, where h is Planck’s constant, c is the speed of light, and λ is the wavelength.

Photon energy is most commonly expressed in electronvolts (eV) or joules (J). 1 eV equals approximately 1.602 × 10⁻¹⁹ J.

Photon Energy refers to the energy carried by a single photon, which is a particle of light or electromagnetic radiation. This energy depends on the photon’s frequency or wavelength.

Formula for Photon Energy

E= h⋅f

  • E = Energy of the photon (in joules, J)
  • h = Planck’s constant = 6.626×10−34 J\cdotps
  • f = Frequency of the photon (in hertz, Hz)

Alternatively, since frequency and wavelength are related by f=cλf

  • ccc = Speed of light = 3.00×108 m/s
  • λ = Wavelength (in meters)

Photon Energy by Wavelength Example

Wavelength (nm)Type of LightPhoton Energy (eV)
700Red Light1.77 eV
550Green Light2.25 eV
400Violet Light3.10 eV
100Ultraviolet (UV)12.4 eV

Conversion: 1 eV=1.602×10−19 J

Applications of Photon Energy

  • Solar Cells: Convert photon energy into electrical energy.
  • Photosynthesis: Plants absorb photons to drive chemical reactions.
  • Lasers: Emit light with specific photon energies.
  • X-ray Imaging: High-energy photons penetrate the body for diagnostics.