Room Acoustics Software

REW is free room acoustics analysis software for measuring and analysing room and loudspeaker responses. The audio analysis features of REW help you optimise the acoustics of your listening room, studio or home theater and find the best locations for your speakers, subwoofers and listening position. It includes tools for generating audio test signals; measuring SPL and impedance; measuring frequency and impulse responses; measuring distortion; generating phase, group delay and spectral decay plots, waterfalls, spectrograms and energy-time curves; generating real time analyser (RTA) plots; calculating reverberation times; calculating Thiele-Small parameters; determining the frequencies and decay times of modal resonances; displaying equaliser responses and automatically adjusting the settings of parametric equalisers to counter the effects of room modes and adjust responses to match a target curve.


The current version is V5.16, 21st May 2016. To view the REW revision history click here.
OS Downloads
Windows installer with JRE (30.7MB, includes private Java 8 runtime)
Recommended for most users unless running Windows XP

Windows installer (14.5MB, requires separate Java 7 or 8 installation)
Recommended for Windows XP or if Java 7 or 8 is already installed

Windows installer with JRE allowing multiple instances (30.7MB)
Allows multiple REW instances to run at the same time
10.7 - 10.11
OS X DMG (31.6MB, includes private Java 8 JRE)
Linux Linux installer (12.4MB, requires Java 7 or 8)
The Oracle Java runtime seems to work best
All Sampledata.mdat (8.0MB)
Sample measurement data


If you find REW useful you can make a donation by clicking the button below. Many thanks to those who have already donated, your generosity keeps REW development going and is greatly appreciated.

Help Files

The REW room acoustics software contains comprehensive help information. You can also view the help files online, download the html files for offline viewing (6.7MB) or download a PDF copy (9.3MB, courtesy of Steve Bolser). For additional tips and assistance in using the software visit the Home Theater Shack REW forum.


Reference Material