Created By : awnish

Reviewed By : Rajashekhar Valipishetty

Last Updated : Apr 10, 2023

Photon Energy Calculator makes use of the radiation frequency to provide the energy of a photon in a short span of time. Just you have provide either frequency or wavelength details to get the wavelength or frequency along with the photon energy as result easily.

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Wavelength of photon(λ):

How to Find Energy of a Photon?

Get the simple and manual steps for calculating the energy of a photon easily.

  • Find the wavelength of the photon.
  • Multiply the speed of the light by Planck's constant.
  • Divide the product by the wavelength to see the energy of a photon.

Photon Energy Formula

A photon is the smallest discrete amount or quantum of electromagnetic radiation. Photon energy depends on frequency and wavelength.

Photon energy is nothing but the energy carried by a photon. The amount of energy emitted is inversely proportional to the wavelength and directly proportional to the electromagnetic frequency of a photon. So, the higher frequency results in higher energy.

The energy of a photon is described by Planck's equation

E = h x c / λ = h x f

f = h x E

λ = h x c/E


E is the energy of a photon

h is the Planck's constant = 6.6261 x 10-34 J.s

c is the speed of the light

f is the frequency of a photon

λ is the wavelength of photon


Question: Calculate the approximate photon energy, frequency if the wavelength of photon is 3 nm.


Given that

Photon wavelength λ = 3 nm

Energy of a photon formula is E = h x c

E = (6.6261 x 10-34 x 299 792 458)/3

E = 0.4132823 meV

Frequency f = h x E

f = 6.6261 x 10-34 x 0.4132823

= 99.93 GHz

Therefore, the frequency of photon is 99.93 GHz, photon energy is 0.4132823 meV.

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FAQ's on Photon Energy Calculator

1. How to calculate the energy of a photon?

The photon energy can be calculated from its wavelength or frequency. Divide the Planck's constant by frequency or multiply Planck's constant and light speed and divide the result by wavelength to obtain the energy value.

2. What is the wavelength of the photon formula?

The wavelength of the photon formula is λ = h x c/E. Here, c is the speed of the light, E is the photon energy and h is the Planck's constant.

3. What does photon energy depend on?

The energy of a photon depends on the radiation frequency or wavelength. By increasing the frequency, photon energy also increases. By decreasing the wavelength, the energy of photons increases.

4. How to use the Photon Energy Calculator?

Give either wavelength or frequency details in the Energy of Photon Calculator fields and hit the calculate blue colour button to get the energy and another parameter in the output section with a clear explanation.