For songwriters & musicians
The Musician Toolkit
Free music theory tools for songwriters, composers, and musicians.
Song Key Finder
Find the key of any song from its chords or audio.
Open ToolChord Transposer
Move any chord progression into a new key instantly.
Open ToolScale Finder
Explore notes, intervals, and chords for any scale.
Open ToolProgression Generator
Generate chord progressions in any key, mood, and length — with playback.
Open ToolCircle of Fifths
Interactive diagram with key signatures, diatonic chords, and a plain-English explainer.
Open ToolChord Decoder
Type any chord symbol and see its notes, intervals, mood, and meaning instantly.
Open ToolWhy The Musician Toolkit?
- 100% Free
Every tool is free, no signup, no paywall, no limits.
- Instant Results
Type, click, done — answers appear the moment you stop typing.
- Built by Musicians
Designed by working songwriters who actually use these tools daily.