Enter your room dimensions to calculate its room modes, the reverberation time (RT60) and where to place your seat and speakers.
A free room acoustics calculator: from your room's length, width and height it works out the room modes (the bass resonances), the RT60 reverberation time and the best seat and speaker placement. Everything runs in your browser.
The three calculators
Room modes show the bass frequencies your room emphasises. RT60 (Sabine) estimates how «live» it is. Placement uses the 38% rule for the listening spot and an equilateral triangle for the speakers. It assumes a rectangular room, so treat it as a guide.
Frequently asked questions
What are room modes?
Standing waves between parallel walls that make some bass notes much louder (peaks) and others almost disappear (nulls), depending on where you sit. They are the main reason a room sounds boomy or uneven in the bass.
What RT60 should I aim for?
For a small listening room or home studio, roughly 0.3–0.5 seconds, fairly even across frequencies. Living rooms are often higher; very dead rooms can feel unnatural. RT60 here uses the Sabine formula and an average absorption.
Why sit at 38% of the room length?
That position tends to avoid the worst peaks and nulls of the main length modes, giving smoother bass. It is a well-known starting point — then fine-tune by ear or with measurements.
How accurate is this?
It is a guide. The maths assumes a rectangular room with rigid walls and uniform absorption; real rooms have doors, windows and furniture. Use it to understand and start, not as a substitute for measuring.