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Science & Engineering

Wavelength and Frequency Calculator

Convert between wavelength and frequency for light, radio and sound, with period and photon energy.

Your inputs

Results

Wavelength

2.99792458E0 m

Period
1E-8 s
Photon energy (electromagnetic waves)
6.62607E-26 J
Photon energy
4.13567E-7 eV

✓Exact calculation — rounded only for display

What this calculator does

For any wave, speed = wavelength × frequency. For light, photon energy is proportional to frequency.

Formula and method

v = λ × f; T = 1 ÷ f; E = h × f (h = 6.62607015 × 10⁻³⁴ J·s)

Worked example

Calculated by this tool with its default inputs:

Inputs

  • I know the: Frequency
  • Frequency: 100000000 Hz
  • Medium: Vacuum (c)

Results

  • Wavelength: 2.99792458E0 m
  • Period: 1E-8 s
  • Photon energy (electromagnetic waves): 6.62607E-26 J
  • Photon energy: 4.13567E-7 eV

How to read the results

Higher-frequency light has shorter wavelengths and more energetic photons.

Assumptions and limitations

  • Refractive indices are typical values; sound speed assumes air at 20 °C.

These are educational estimates. Electrical, structural and other safety-critical work must comply with local codes and be designed or checked by a qualified professional.

Questions

What is the wavelength of FM radio?

About 3 m at 100 MHz.

Sources

Methodology and verification

Result type
Exact mathematical calculation (rounded only for display)
Formula version
1.0
Automated verification
3 reference and validation test cases, checked against independently computed values. The site cannot be built if any of them fail.
Editorial review
Awaiting human editorial review. The explanation was drafted with AI assistance; the formula and examples are verified by the automated tests above.

Privacy

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