Tools
Theory, put to work
The reference pages tell you what an interval, a chord or a scale is. The tools are for the moment you have a real progression in front of you and need to do something with it — transpose it, name it, or find its key.
The tools
One tool for each job a musician actually has to do with theory. Each works on any instrument the site knows, and every result can be heard.
- Harmony
Chord transposer
Paste a progression in any key and read it back in another, as chord symbols or roman numerals, and hear it on your instrument.
Available - Harmony
Roman numeral converter
Type chords and read them as roman numerals, or type numerals and read them as chords in any key.
Available - Keys
Key finder
Enter the chords of a song and see which keys they fit, which chord is doing what, and where the borrowed ones come from.
Available - Harmony
Chord identifier
Play or type a handful of notes and get the chord they spell, its inversions, and the other names it goes by.
Available - Scales
Scale finder
Pick the notes of a melody or riff and find every scale that contains them, from the major scale to the modes and beyond.
Available - Intervals
Interval calculator
Two notes in, an interval out — or a note and an interval in, and the note that lands. With the sound of it, both ways.
Available - Keys
Interactive circle of fifths
Turn the circle to any key and read off its scale, its diatonic chords, its neighbours and its relative minor.
Available
Go deeper
What the tools compute, the reference pages explain — with every chord, scale and progression on its own page.
Progressions in every key
Each progression page lists its chords in all twelve keys — a transposition table you can hear.
Chord library
Look a chord up by symbol and see its notes, its shape on your instrument and the scales it belongs to.
Scales and modes
Every scale with its notes, its pattern on piano and guitar, and the chords built on each degree.
Missing a tool?
If there is a step in your workflow you keep doing by hand, describe it. The list above is a starting point, not a plan carved in stone.