The whole system, in one place.
Chordii started as a set of chord-reference cards built around the circle of fifths. The app is all of it — and then more than all of it. Every key, every chord, every substitution, every progression, in your pocket. If you own the cards, this is their companion. If you don't, it's everything on its own.
(psst, watch the video)
Pick a key. See everything.
Start with the full key in front of you: every chord around the circle of fifths, light for major, dark for minor. Change key with a drag — the grid shifts and settles like the original wheel. Everything in one view, waiting to be tapped when you're ready to go deeper.
Tap a chord, understand a chord.
Every chord opens up: its notes, what it's doing in the key, the extensions that change its color, and substitutions when you want a different feeling — including borrowed chords from outside the key, clearly marked. Less "here's the theory," more "here's how it feels."
Find a progression by how it should feel.
Browse curated progressions by mood — uplifting, melancholic, brooding, epic — in major or minor, in any key. When you'd rather write your own, the builder gives you up to eight slots and suggests where to go next as you fill it in.
Four tools for when you're actually playing
Capo, Transpose, Turnarounds, and Parallel Minor — the practical lookups you need mid-session, each one a quick reference, no digging.
Yours. No strings.
This is the part I care about most. I'm tired of renting software. Tired of ads. Tired of opening an app to make something and getting sold something instead. Chordii doesn't do any of it. Buy it once and it's yours. No subscription, no ads — ever. Nothing inside it will ever try to sell you anything.
Install it to your home screen, sign in once, and it works offline. Nothing in your way. Just you and the chords.





