Scaler Music has released Scaler Detector, a standalone app and plugin for macOS and Windows that detects the key, scale, and chords of any audio or MIDI you feed it. It’s available now for just $9, or completely free for Scaler 3 owners.
Scaler Detector takes the same powerful detection engine found in Scaler 3 and wraps it in a lightweight package that is adapted for quick harmonic analysis, ear training, or exploring your own chord progressions.
You can load it as a VST, AU, or AAX plugin inside your DAW or run it standalone to focus purely on theory and composition.
The concept is simple, but I found it incredibly useful. You basically play or drag in any audio or MIDI file, and Scaler Detector instantly displays the matching chords and the most likely scales, complete with mood descriptors like serious, sad, or bright.
It’s super handy for figuring out the key of a sample pack loop, a whole song, or even a rough idea played on your MIDI keyboard.
Once a scale is detected, you can trigger its diatonic chords directly from your keyboard using Bind Keys, which makes one-finger chord progressions possible in seconds.

As a nice bonus, there’s also a Voice Grouping option that automatically keeps all the chord voicings within a similar range, giving everything a smoother and more musical sound.
You can click on any detected chord to audition it, or simply drag and drop chords straight from the interface into your DAW’s timeline. It even works as a real-time monitor that shows what you’re playing in the chord panel, even when the detector isn’t actively recording.
For me, the best part is how instant everything feels. I tried it on a few guitar chord progressions I recorded several months ago, and Scaler Detector immediately rediscovered their harmonic structure (and that instantly reminded me what I was playing at the time).
It’s also a fun way to analyze songs you love and find ideas for your own projects. You just need to route the audio from Spotify or YouTube into Scaler Detector and see what’s really going on harmonically.
Scaler Detector is available now for $9 or free for Scaler 3 users (log in to your Scaler Music account to redeem). It runs on macOS 10.14 or later (Apple Silicon compatible) and Windows 8 or higher, in VST, VST3, AU, and AAX plugin formats, as well as standalone.
Product page: Scaler Detector ($9, FREE for Scaler 3 owners)
More:
- Scaler Music Releases Scaler 3.1 – A Powerful Update to Its Flagship Music Theory Plugin
- Higher Plane releases SpaceWalk, a FREE ambient chord progression generator
Last Updated on October 29, 2025 by Tomislav Zlatic.





