Photon Energy Calculator
Calculate photon energy instantly in your browser — the published formula, worked locally with no data sent anywhere.
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What this tool does
Calculate photon energy instantly in your browser — the published formula, worked locally with no data sent anywhere. Energy of a single photon. Total beam power also depends on how many photons per second arrive — a bright radio source can carry more total power than a faint X-ray beam despite each radio photon being far weaker.
How to use the Photon Energy Calculator
- Enter or select given.
- Enter or select wavelength (nm).
- Enter or select frequency (hz).
- Read the calculated result; change any measurement to compare alternatives.
Formula
photon energy E = h × f = h × c / λ, with Planck's constant h = 6.62607015×10⁻³⁴ J·s. A handy shortcut: E (eV) ≈ 1240 / λ (nm).
- mode
- Given
- lambda
- Wavelength (nm)
- freq
- Frequency (Hz)
Energy of a single photon. Total beam power also depends on how many photons per second arrive — a bright radio source can carry more total power than a faint X-ray beam despite each radio photon being far weaker.
Worked example
For photon energy calculator, the following measurements illustrate the exact method: Given: wavelength; Wavelength (nm): 500; Frequency (Hz): 599600000000000.
Inputs
- GivenWavelength
- Wavelength (nm)500
- Frequency (Hz)599600000000000
Result
- Photon energy (eV)2.48
- Photon energy (J)0
- Frequency (Hz)599,584,915,999,999.9
- Wavelength (nm)500
- Energy per mole of photons (kJ/mol)239.25
- Spectrum regionVisible light
Results explained
- Photon energy (eV)
- Photon energy (eV) from the formula above. Energy of a single photon. Total beam power also depends on how many photons per second arrive — a bright radio source can carry more total power than a faint X-ray beam despite each radio photon being far weaker.
- Photon energy (J)
- Photon energy (J) from the formula above. Energy of a single photon. Total beam power also depends on how many photons per second arrive — a bright radio source can carry more total power than a faint X-ray beam despite each radio photon being far weaker.
- Frequency (Hz)
- Frequency (Hz) from the formula above. Energy of a single photon. Total beam power also depends on how many photons per second arrive — a bright radio source can carry more total power than a faint X-ray beam despite each radio photon being far weaker.
- Wavelength (nm)
- Wavelength (nm) from the formula above. Energy of a single photon. Total beam power also depends on how many photons per second arrive — a bright radio source can carry more total power than a faint X-ray beam despite each radio photon being far weaker.
- Energy per mole of photons (kJ/mol)
- Energy per mole of photons (kJ/mol) from the formula above. Energy of a single photon. Total beam power also depends on how many photons per second arrive — a bright radio source can carry more total power than a faint X-ray beam despite each radio photon being far weaker.
- Spectrum region
- Spectrum region from the formula above. Energy of a single photon. Total beam power also depends on how many photons per second arrive — a bright radio source can carry more total power than a faint X-ray beam despite each radio photon being far weaker.
Frequently asked questions
photon energy E = h × f = h × c / λ, with Planck's constant h = 6.62607015×10⁻³⁴ J·s. A handy shortcut: E (eV) ≈ 1240 / λ (nm).
Energy of a single photon. Total beam power also depends on how many photons per second arrive — a bright radio source can carry more total power than a faint X-ray beam despite each radio photon being far weaker.
Every field is labelled with its unit — enter values in exactly the labelled unit and read the result in the labelled output unit. Fields with a unit symbol also support the site-wide imperial/metric switch, which converts before the formula runs.
It uses double-precision arithmetic and the published constants and formulas named on this page. The last displayed digit may be rounded, and real conditions can differ from the idealized model described in the assumptions.
Yes. Every calculation runs entirely in your browser; nothing you enter is uploaded, stored or shared.