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Both calculators run independently — change the inputs on either side to compare results.
Relativity
Relativistic Doppler Shift Calculator
Calculates the observed frequency of light or sound when source and observer move at relativistic speeds. Use it when relative velocity is a significant fraction of the speed of light.
Fill in the required fields to see your result.
Relativity
Relativistic Doppler Effect Calculator
Compute the observed frequency and wavelength when a light source moves toward or away from you at relativistic speeds. Used in astrophysics to analyze spectra of fast-moving stars, galaxies, and spacecraft.
Fill in the required fields to see your result.
Key differences
| Relativistic Doppler Shift Calculator | Relativistic Doppler Effect Calculator | |
|---|---|---|
| Category | Relativity | Relativity |
| Inputs required | 3 | 3 |
| Result | Observed Frequency (Hz) | Observed Frequency (Hz) |
| What it does | Calculates the observed frequency of light or sound when source and observer move at relativistic speeds. Use it when relative velocity is a significant fraction of the speed of light. | Compute the observed frequency and wavelength when a light source moves toward or away from you at relativistic speeds. Used in astrophysics to analyze spectra of fast-moving stars, galaxies, and spacecraft. |