ClarityHow to use this tool
- Enter photon frequency in hertz; scientific notation such as 5e14 is accepted.
- Calculate energy per photon in joules and electronvolts.
- Use the wavelength result for propagation in vacuum.
Input reference and sample values
Use the units and choices shown for each field. Sample values are provided for practice, not as recommendations.
| Input | Format and units | Sample |
|---|---|---|
| Frequency | Numeric value. Unit: Hz. Must be greater than zero. | 500000000000000 |
Result for these sample inputs
3.31303508e-19 J
- Energy (eV)
- 2.06783385
- Vacuum wavelength (nm)
- 599.584916
Select Try the example in the form to load these values and calculate them again. This replaces the current form inputs. Compare the result with the method and worked explanation below.
The method, explained
Energy = Planck constant × frequency; h = 6.62607015 × 10⁻³⁴ J·s.
At 5 × 10¹⁴ Hz, one photon carries 3.313035075 × 10⁻¹⁹ J, approximately 2.067834 eV. Its vacuum wavelength is 599.584916 nm.
What to keep in mind
Energy is per photon, not beam power. Vacuum wavelength uses c = 299,792,458 m/s; wavelength in a material depends on its refractive index.
Reference: SI defining constants — NIST
Common questions
Is this the total energy of a laser pulse?
No. Multiply energy per photon by the number of photons to obtain total energy.
Does wavelength change inside glass?
Yes. Frequency remains unchanged across a stationary boundary, while propagation speed and wavelength depend on the medium.
Methodology maintained by ClarityKit. How these tools are built and checked.