Disclaimer

Last updated: June 2026

The tools, content, and resources provided on Reverb-Calculator.com are intended for general educational and informational purposes only. The website is operated by Noah Bennett (contact available via the Contact page).

By using this website, you acknowledge and agree to the limitations described in this Disclaimer.

1. Educational Purpose Only

Reverb-Calculator.com provides browser-based RT60 calculation tools and educational content about reverberation time, acoustic formulas, absorption coefficients, and room design targets. All content is intended to support learning, planning, and general acoustic reference — not to replace professional acoustic consultation, certified acoustic measurement, or formal acoustic engineering services.

This website does not provide:

Professional acoustic consulting or engineering services
Certified acoustic measurements per ISO 3382 or any other standard
Construction specifications, material procurement guidance, or installation advice
Regulatory compliance verification for acoustic performance standards

For more about the site’s purpose, see the About page.

2. Calculation Accuracy and Model Assumptions

The RT60 calculators on this site apply the Sabine and Eyring formulas to user-entered room dimensions and absorption coefficient values. The mathematical computation is exact — but the formulas are models based on simplifying assumptions, and real rooms may deviate from those assumptions in ways that cause the calculated RT60 to differ from the measured RT60.

Sabine formula assumptions and limitations:

The Sabine formula (RT60 = 0.161 × V/A) assumes:

A diffuse sound field — sound energy arriving at all points from all directions with equal probability. In practice, sound fields in rooms are rarely fully diffuse, particularly in small rooms or rooms with irregular geometry.
Uniformly distributed absorption — absorptive materials spread evenly across all surfaces. A room with all its absorption concentrated on one wall will have a different acoustic behaviour from one where the same total absorption is evenly distributed.
Standard geometry — the formula performs best in approximately rectangular rooms with near-uniform surface treatment.

The Sabine formula also overestimates RT60 for rooms with high average absorption (mean coefficient above approximately 0.30). For such rooms — including recording studios, vocal booths, and heavily treated home theatres — the Eyring formula provides more accurate results.

Eyring formula:

The Eyring formula (RT60 = 0.161 × V / (−S × ln(1−ᾱ))) corrects for the non-linearity of the absorption-reverberation relationship at high absorption values. However, it shares the same diffuse field and geometric assumptions as the Sabine formula.

Both formulas cannot predict:

Flutter echo — rapid repetitive reflections between parallel surfaces, which are not captured by RT60 and require geometric analysis
Room modes — standing wave resonances at low frequencies determined by room dimensions
Frequency-specific RT60 — unless each octave band is calculated separately with frequency-specific absorption coefficients
The effect of irregular geometries — domed ceilings, angled surfaces, curved walls, or complex architectural features

3. Absorption Coefficient Data

The accuracy of any RT60 calculation depends entirely on the absorption coefficient values entered. Users should be aware that:

Published absorption coefficient values are measured under laboratory conditions and may not perfectly match real-world performance due to installation differences, surface area, mounting method, and room geometry
Absorption coefficients vary with frequency — the single coefficient entered into the calculator represents an average across frequencies, which may not reflect the room’s actual frequency-dependent behaviour
Coefficients from different published sources may vary for nominally the same material

Using approximate or incorrect absorption coefficients will produce correspondingly approximate or incorrect RT60 results.

4. Not a Substitute for Professional Measurement

Calculated RT60 estimates from the Sabine and Eyring formulas are not equivalent to measured RT60 values obtained through proper acoustic measurement per ISO 3382. Professional acoustic measurement uses a calibrated omnidirectional sound source, calibrated measurement microphones, and specialised impulse response analysis software to produce reliable, traceable results.

Calculated estimates are appropriate for:

Initial acoustic planning and design exploration
Estimating the effect of proposed acoustic treatment changes
General educational understanding of RT60 and room acoustics
Rough acoustic assessment for non-critical applications

Calculated estimates are not appropriate for:

Formal acoustic certification or compliance documentation
Legal or contractual acoustic performance specifications
Construction contracts where specific acoustic performance is guaranteed
Critical professional acoustic design where ISO 3382 measurement is the standard

5. No Professional Advice

Reverb-Calculator.com does not provide professional acoustic engineering, architectural acoustics consulting, building physics services, or construction guidance. Acoustic treatment decisions — particularly those involving significant construction, material costs, or professional performance requirements — should involve a qualified acoustic engineer or consultant.

6. No Warranties

The website and its tools are provided on an “as is” basis without warranties of accuracy, fitness for a particular purpose, or availability.

7. Limitation of Liability

To the maximum extent permitted by applicable law, Noah Bennett and Reverb-Calculator.com are not liable for:

Acoustic treatment decisions made based on calculated RT60 estimates
Discrepancies between calculated and measured RT60 values
Construction or treatment costs based on tool results or educational content
Decisions made based on absorption coefficient data or room design target information
Technical failures, downtime, or performance issues
Any direct, indirect, incidental, or consequential damages arising from use of this website

Use of this website is entirely at your own discretion and risk.

8. Updates to This Disclaimer

This Disclaimer may be updated periodically. The effective date at the top of this page will reflect the most recent revision. Continued use after an update constitutes acceptance.