Practical tools for measured work
RT60 & Reverberation Time Calculator
Estimate Sabine reverberation time and the total absorption needed for an editable decay target.
A metric sabin is one square metre of perfectly absorbing surface. Real materials contribute area multiplied by their frequency-dependent absorption coefficient.
How it works
How to use it: enter internal room dimensions and estimated total absorption at the frequency band of interest. Set a target to estimate how much absorption that target requires.
Formula. Sabine RT60 = 0.161 x room volume / total absorption.
Example. A 62.4 m3 room with 35 sabins has an estimated RT60 of 0.29 seconds.
Current-input example
The result above uses these exact values. This snapshot is included when the page is printed so the output can be checked against the original measurements.
- Room length
- 5.5 m
- Room width
- 4.2 m
- Room height
- 2.7 m
- Total absorption
- 35 sabins
- Target RT60
- 0.4 s
Primary result: Estimated RT60: 0.29 s.
Before using the result
- Measure from the datum or reference edge described by this tool, and do not mix inside, outside and centerline dimensions.
- Keep inputs in the displayed units and preserve more precision than the final cutting or purchasing tolerance requires.
- When the result is close to a limit, verify it with a test piece, field measurement, manufacturer drawing or qualified project professional.
Limitations
Sabine assumes a diffuse sound field and reasonably even absorption. Small rooms, sparse treatment, low frequencies and highly absorptive rooms can depart substantially. Use band-specific material data and confirm with a calibrated decay measurement.
Frequently asked questions
What RT60 should a home theater have?
There is no single universal target. Room size, listening use and measurement band matter, so compare against a considered design target rather than treating one number as a pass or fail.
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