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Chord progression builder

Start with one chord and the tool suggests what comes next — three moves the style leans on, two with more colour in them, each with the reason it works. Click a chord to hear it, add it if you like it, and change key any time without losing your place.

Genre
Key
Tempo
90bpm

Versein C major

Nothing in the verse yet. Pick one of the openers below to start — the tonic is the safe one, but any of them works.

Start here

How rock/pop songs usually open

Try something

Borrowed chords and secondary dominants — less expected, still right

How to use it

  • The Roman numeral under each chord is what it's doing in the key. Learn songs by those numbers and you can play them anywhere.
  • Change the key at any point. The chords are stored as numbers, so the names update and the progression stays exactly as you built it.
  • Four bars is a phrase. When you're one chord from filling one, the suggestions lean toward the chords that land it.
  • Every chord holds four beats — a bar — until you say otherwise. The − and + under a chord change how long it rings, from a single beat to four bars, which is how a line stops sounding like a metronome.
  • Verse, chorus and bridge are three separate lines. Build one, click another and build that, then tick the parts you want and Play runs them in order. Untick the verse to work on the chorus alone.
  • “Try something” is where borrowed chords and secondary dominants live — the ones that make a progression sound written rather than assembled.
  • “Add your own” takes any chord you like, in the key or well outside it. Add one and the suggestions carry on from it — a dominant chord gets offered the chord it's leaning on, even when that chord belongs to another key.

Not sure how a chord is fingered? The chord library has every shape →