Free · Physics models
Vacuum Photon Frequency, Wavelength and Energy
Convert photon wavelength, frequency and energy using the current exact SI defining constants and a local scientific-notation display.
- Formula & worked example
- Private in your browser
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Calculator inputs
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How to use this calculator
- Enter the known values in the units shown. Results update as you type.
- Where results are editable, change one to solve backwards. Lock a value to hold it fixed.
- Use the worked example to check the method. Reset restores the starting fields.
Private by default
Inputs and results stay in this browser tab. Bookify does not upload or store the values you enter.
Formula and method
At 1 GHz, photon energy is 6.62607015×10⁻²⁵ joule and wavelength is 299.792458 millimeters.
E=hf, wavelength=c/f; h=6.62607015×10⁻³⁴ J·s, c=299792458 m/s, 1 eV=1.602176634×10⁻¹⁹ J.
Worked example
Enter these known values and leave the other values blank.
- Frequency
- 1 GHz
- Wavelength
- 299.7925 mm
- Energy
- 0.004135668 meV
Assumptions and limitations
- These are vacuum wavelength/frequency relations for a single photon. The displayed energy units include electronvolts and their captured submultiples.
- The joule explanation uses three significant digits in its ordinary display band and four significant digits in scientific notation; the unrounded energy remains available.
- A photon in a medium retains frequency while wavelength depends on the medium; this vacuum model does not include dispersion or multiphoton energy.
- Clear the unknown numerical field before using a supported inverse; selection controls retain their captured branches.
Common questions
What assumptions matter for this model?
These are vacuum wavelength/frequency relations for a single photon. The displayed energy units include electronvolts and their captured submultiples.
What does this model leave out?
A photon in a medium retains frequency while wavelength depends on the medium; this vacuum model does not include dispersion or multiphoton energy.
References
Replace the pinned binary-number formatting helpers by standalone decimal scientific notation and update the captured obsolete Planck/charge approximations to their exact 2019 SI definitions. Preserve the ordinary/scientific display bands, rounding precision and all wavelength/frequency/energy inverses.