Science & Engineering

Doppler Effect Calculator (Sound and Light)

Calculate the Doppler shift for sound waves and for electromagnetic waves with the relativistic formula. It includes air, water, and custom media plus redshift z for astronomy.

How to use
  1. Choose sound waves or electromagnetic waves.
  2. Enter the source frequency and the relevant speeds.
  3. Pick a medium for sound, or enter velocity for light.
For study and estimation. Verify against authoritative data before relying on a result.
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Common questions

Why does a passing siren change pitch?

As the source moves toward you the sound waves bunch up and the pitch rises, then it drops as the source moves away. That is the Doppler effect.

What is redshift z?

It measures how much light from a moving source is stretched to longer wavelengths. Astronomers use it to gauge how fast distant objects recede.

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