Reverb Time (RT60) Calculator
Fill in the values and the answer updates as you type.
How the Reverb Time (RT60) Calculator works
Sabine's formula: RT60 = 0.161 × volume ÷ total absorption, where total absorption = surface area × average absorption coefficient. RT60 is the time for sound to fall by 60 dB. The formula is most accurate in fairly live rooms with absorption coefficients below about 0.3. The character labels are broad guidelines, not standards. Example: with Room volume 54 m³, Total surface area 88.6 m², and Average absorption coefficient 0.25 (0–1), the result is Reverb time RT60 (s) = 0.39; Room character = Controlled (recording and mixing); Extra absorption needed for target (m² sabins) = 0.
Inputs and results
The Reverb Time (RT60) Calculator takes 4 inputs and gives 4 results.
What you enter
- Room volume (m³) — starts at 54.
- Total surface area (m²) — starts at 88.6.
- Average absorption coefficient ((0–1)) — starts at 0.25.
- Target RT60 (s) — starts at 0.4.
What you get
- Reverb time RT60 (s)
- Room character
- Extra absorption needed for target (m² sabins)
- Total absorption now (m² sabins)
Example: Reverb Time (RT60) Calculator with the starting values
With room volume 54 m³, total surface area 88.6 m², average absorption coefficient 0.25 (0–1) and target rt60 0.4 s, the calculator returns:
| Reverb time RT60 (s) | 0.39 |
|---|---|
| Room character | Controlled (recording and mixing) |
| Extra absorption needed for target (m² sabins) | 0 |
| Total absorption now (m² sabins) | 22.2 |
Change any value above and the results update straight away.
Reverb Time (RT60) Calculator FAQ
How do I use the Reverb Time (RT60) Calculator?
Enter room volume, total surface area, average absorption coefficient and target rt60 in the fields, then read reverb time rt60 (s), room character, extra absorption needed for target (m² sabins) and total absorption now (m² sabins) in the result panel. The answer updates as you type, and you can press Calculate or Enter to refresh it. Use “Copy link” to share your exact numbers with someone else.
What does the Reverb Time (RT60) Calculator calculate?
Sabine reverberation time and the absorption needed to reach a target. It returns reverb time rt60 (s), room character, extra absorption needed for target (m² sabins) and total absorption now (m² sabins) from the 4 values you provide.
What values does the Reverb Time (RT60) Calculator start with?
It opens with room volume 54 m³, total surface area 88.6 m², average absorption coefficient 0.25 (0–1) and target rt60 0.4 s so you can see a working result straight away. Replace them with your own numbers, or press Reset to return to these starting values.
Is the Reverb Time (RT60) Calculator free and private?
Yes. It is free, needs no account, and runs in your browser, so nothing you type is sent to or stored on our servers. See the Privacy Policy for details.
Can I rely on the Reverb Time (RT60) Calculator for important decisions?
Treat the result as a well-rounded estimate. Real situations often have details a general calculator cannot know, so confirm important decisions with a qualified professional. See the Disclaimer for more.