Free master comparison: Choose the better master by sound, not volume.
Compare two audio files of the same song at matched loudness: the master you were sent against the one you had, or two engineers’ versions.
What you get
- A fair listening test. Both versions play at matched loudness, so level does not decide for you.
- See what actually changed. Loudness, true peak, range, tone balance and stereo width for each file.
- Know what streaming does to each. How far apart they land after Spotify’s normalisation, and which peaks leave no room for an encoder.
- Keep unreleased music private. Both files are measured in your browser; nothing is uploaded.
Or try a sample pair
A personal mastering sample’s mix and master — the only same-song pair the site publishes. The tool is meant for two masters.
What this measures, and what it cannot tell you
Everything here is measured from the audio itself: loudness, true peak, range, tone balance, stereo width, and the marks a lossy encoder leaves behind. Those are facts about the file.
Which master is better is not a fact about the file. A quieter, more dynamic master is right for one song and wrong for the next; a brighter one suits one mix and fatigues on another. This page tells you what is different and what each difference will do on a streaming service. The choice stays yours.
Take the loudness advantage out of the comparison.
Use two masters of the same song. Loudness matching helps you hear differences in tone, dynamics and stereo without automatically favoring the louder version. The readings describe the files; they do not rank the musical quality of a master.
