About the Echo Time Calculator
Time for an echo to return from a surface, or the distance to the wall from the echo delay.
Also known as: echo distance, sonar calculator, reverberation time.
How to use this calculator
- Enter calculate, speed of sound.
- The result updates instantly as you type — press Calculate (or Enter) at any time.
- Review the breakdown shown under the main result.
- Use Copy result or Share to save the answer or send a link with your inputs.
Formula
distance = speed × delay ÷ 2
Worked example
Using the values pre-filled in the calculator above:
- Calculate: Echo delay
- Distance to surface = 100 m
- Speed of sound = 343 m/s
the calculator returns:
- Echo delay: 0.5831 s
- Round-trip distance: 200 m
- Distinct echo?: Yes — over 0.1 s, heard as a separate echo