Reverberation Time Calculator – Acoustic RT60 Tool
Model your room's acoustics and visualize the decay time with this professional analysis dashboard.
Room Modeler
Enter your room data to analyze its acoustic profile.
How to Use the RT60 Calculator
Get an accurate estimate of your room's reverberation time with our simple three-step process.
Enter Dimensions
Input the length, width, and height of your room in meters. This is used to calculate the total volume.
Select Materials
Choose the primary material for the walls, floor, and ceiling from the dropdown menus.
Analyze the Results
Click "Analyze" to see the calculated RT60, total absorption, and a visual representation of the sound decay time.
What is Reverberation Time?
RT60 is a scientific measurement of how long it takes for a sound to "decay" or fade away in a space. It's a critical factor in the acoustic design of any room.
The Technical Definition
Specifically, RT60 is the time it takes for the sound pressure level in a room to drop by 60 decibels (dB) after the sound source has stopped. A long RT60 means a "live" room with many echoes, while a short RT60 means a "dead" or "dry" room with few reflections.
Sabine's Formula
Our calculator uses the Sabine Formula, the industry-standard equation for estimating RT60. It relates the room's volume to the total sound absorption of its surfaces. Rooms with a larger volume and hard, reflective surfaces will have a longer RT60.
Ideal RT60 for Different Spaces
The "perfect" reverberation time depends entirely on the intended use of the room. Our calculator provides insights to help you understand your results.
Recording Studios
(0.2 - 0.6 seconds)
Vocal booths and mixing rooms require a very "dry" sound with minimal reflections to capture clean audio and make accurate mixing decisions.
Classrooms & Lecture Halls
(0.6 - 0.9 seconds)
The primary goal is speech intelligibility. Too much reverb can make it difficult for students to understand the speaker.
Concert Halls
(1.5 - 2.5 seconds)
A longer reverberation time is desirable for classical music, as it adds richness, warmth, and a sense of envelopment to the performance.
Frequently Asked Questions
Get quick answers to common questions about acoustics and reverberation time.
What is a "Sabin"?
The Sabin is the unit of sound absorption. One square meter of a perfectly absorptive material (that absorbs 100% of sound) has a value of one Sabin. Our calculator determines the total absorption of your room in Sabins by multiplying the area of each surface by its absorption coefficient.
How can I reduce the reverberation time in my room?
To reduce RT60, you need to add more sound-absorptive materials to the space. This can include thick carpets and rugs, heavy curtains, upholstered furniture, bookshelves filled with books, or dedicated acoustic treatment like foam panels or bass traps. Experiment with the materials in our calculator to see how they impact the final result.
Does the shape of the room matter?
Yes, immensely. The Sabine formula used in this calculator assumes a relatively rectangular room where sound is distributed evenly. Rooms with irregular shapes, domed ceilings, or parallel walls can create complex acoustic problems like flutter echoes or standing waves that this simple formula cannot predict. However, it still provides an excellent baseline for understanding the overall reverberation of the space.