What is the best free mastering tool for Mac?

Checked September 2026 · 11 picks · 11 compared

Best Free Mastering Tools for Mac (2026)

The best free mastering tools for Mac are OTT, HoRNet Magnus Lite and Ozone Imager. OTT is best for aggressive multiband upward/downward compression. HoRNet Magnus Lite is best for loudness limiting. Ozone Imager is best for checking and adjusting stereo width.

#1Xfer Records
OTT
FREE
Free three-band upward/downward multiband compressor originally from Ableton's Multiband Dynamics preset.
VST3supportedAUsupportedAAXsupportedCLAPnot supportedWINsupportedMACsupportedLNXnot supported
#2HoRNet
HoRNet Magnus Lite
FREE
A free limiter and clipper.
VST3supportedAUsupportedAAXsupportedCLAPnot supportedWINsupportedMACsupportedLNXnot supported
#3iZotope
Ozone Imager
FREE
A free stereo imaging plugin with width control and vectorscopes.
VST3supportedAUsupportedAAXsupportedCLAPnot supportedWINsupportedMACsupportedLNXnot supported
#4Tokyo Dawn Records
TDR Kotelnikov
FREE
Free wideband mastering compressor combining high fidelity control with musical flexibility.
VST3supportedAUsupportedAAXsupportedCLAPnot supportedWINsupportedMACsupportedLNXnot supported
#5Tokyo Dawn Records
TDR VOS SlickEQ
FREE
Free mixing/mastering EQ with four vintage-modeled EQ character options.
VST3supportedAUsupportedAAXsupportedCLAPnot supportedWINsupportedMACsupportedLNXnot supported
#6Voxengo
Voxengo Marvel GEQ
FREE
A free linear-phase 16-band graphic equalizer suited to mixing and mastering.
VST3supportedAUsupportedAAXsupportedCLAPnot supportedWINsupportedMACsupportedLNXnot supported
#7Voxengo
Voxengo MSED
FREE
A free mid-side encoder/decoder utility.
VST3supportedAUsupportedAAXsupportedCLAPnot supportedWINsupportedMACsupportedLNXnot supported
#8Voxengo
Voxengo Stereo Touch
FREE
A free mid/side stereo widener.
VST3supportedAUsupportedAAXsupportedCLAPnot supportedWINsupportedMACsupportedLNXnot supported
#9Polyverse Music
Wider
FREE
A free stereo widener that stays mono-compatible.
VST3supportedAUsupportedAAXsupportedCLAPnot supportedWINsupportedMACsupportedLNXnot supported
#10Youlean
Youlean Loudness Meter
FREE
A free loudness metering plugin for measuring perceived loudness against TV, streaming and broadcast standards.
VST3supportedAUsupportedAAXsupportedCLAPnot supportedWINsupportedMACsupportedLNXnot supported
#11Youlean
Youlean Loudness Meter 2 Pro
FREEpaid $39+
A loudness meter with streaming presets, dynamics graph and export.
VST3supportedAUsupportedAAXsupportedCLAPnot supportedWINsupportedMACsupportedLNXnot supported

Comparison table

Name	Price	Formats	Runs on
OTTXfer Records	Free	VST3, AU, AAX	Windows, macOS
HoRNet Magnus LiteHoRNet	Free	AU, VST, VST3, AAX	Windows, macOS
Ozone ImageriZotope	Free	AU, AAX, VST2, VST3	Windows, macOS
TDR KotelnikovTokyo Dawn Records	Free	VST3, AU, AAX	Windows, macOS
TDR VOS SlickEQTokyo Dawn Records	Free	VST3, AU, AAX	Windows, macOS
Voxengo Marvel GEQVoxengo	Free	VST, VST3, AU, AAX	Windows, macOS
Voxengo MSEDVoxengo	Free	VST, VST3, AU, AAX	Windows, macOS
Voxengo Stereo TouchVoxengo	Free	VST, VST3, AU, AAX	Windows, macOS
WiderPolyverse Music	Free	VST2, VST3, AU, AAX	Windows, macOS
Youlean Loudness MeterYoulean	Free	VST2, VST3, AU, AAX	Windows, macOS
Youlean Loudness Meter 2 ProYoulean	Free	VST2, VST3, AU, AAX, Standalone	Windows, macOS

Questions people ask

OTT by Xfer Records. It is best for aggressive multiband upward/downward compression and is free to use.