Compton Scattering Calculator
Calculate the wavelength shift of a photon scattered off an electron using the Compton formula.
Input Parameters
Picometers (pm) or nanometers (nm)
0° = forward scattering, 180° = backscattering
Quick angles
Enter a wavelength and angle, then click Calculate.
Wavelength Shift
Δλ
Scattered Wavelength
λ′
Scattered Photon Energy
E′
Calculation Detail
Compton Formula
Δλ = (h / mec) × (1 − cos θ)
Compton wavelength λc = h / mec = 2.42631 pm
Summary
Calculate the wavelength shift of a photon scattered off an electron using the Compton formula.
How it works
- Enter the incident photon wavelength in picometers (pm) or nanometers (nm).
- Enter the scattering angle in degrees (0 to 180).
- The calculator applies the Compton formula: Δλ = (h / m_e c)(1 − cos θ).
- Results show the wavelength shift, scattered wavelength, and scattered photon energy.
Use cases
- Verify textbook Compton scattering problems by computing expected wavelength shifts.
- Explore how backscattering (180 degrees) produces the maximum wavelength shift of ~4.85 pm.
- Calculate scattered photon energies for X-ray or gamma-ray interactions with electrons.
- Understand how the Compton effect demonstrates the particle nature of light.
- Study the relationship between scattering angle and energy transfer to the recoil electron.
Frequently Asked Questions
Last updated: 2026-07-01 ·
Reviewed by Nham Vu