Reference library
Free songwriting reference, organised. Every common chord, every diatonic progression in every key, the open-chord embellishments that turn a plain progression into a song, the arpeggio shapes you'll actually use. Built to be skimmed quickly when you're mid-song, not to teach you music theory cover-to-cover.
Chord progressions in every key
The seven diatonic chords of any key, the six progressions songwriters actually use, the borrowed chords that add colour, the song examples that prove they work. Use it to find a progression in a key you're already playing in, or to transpose one you know.
All 24 keys →Individual chord reference
Every common chord with 10+ voicings (CAGED full shapes, triad shapes, piano voicings), the theory behind it, common progressions including it, and real songs that lean on it. Tap a name to see all of it.
All 50 chords →Open-chord embellishments
The eight open chords (E, A, D, G, C, Em, Am, Dm) with all the safe scale-degree moves that produce named variants (Cmaj7, Csus4, Cadd9, etc), plus the risky ones that need context. The trick every acoustic guitarist learns the slow way, here in one place.
All 8 chords + overview →Arpeggio shapes
The five major CAGED arpeggio shapes (C, A, G, E, D) and their minor versions (Cm, Am, Gm, Em, Dm), each with 4-note and 3-note variations, theory, practice drills, and the songwriting contexts they actually appear in. Plus a 15-minute daily drill plan on the overview.
All 10 shapes + drills →Want a tool instead of a reference?
The reference library is for looking things up. The chord progression builder is for building progressions interactively, RhymeForge for finding rhymes, CollisionLab for breaking out of literal language, Morning Pages for clearing the head before writing, SenseSpark for sensory prompts. All free, all in the browser.