OtoTheory
Your SketchUntitled
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AI Import
1Enter your song
2Copy the prompt
3Paste into AI, generate & copy
4Paste the chord progression
Choose your first chord
C
Tonic (I)
Classic start
Am
Tonic (vi)
Emotional opening
F
Subdominant (IV)
Start with openness
Cmaj7
Tonic (I7)
Add richness
Am7
Tonic (vi7)
Mellow emotion
Fmaj7
Subdominant (IV7)
Dreamy float
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Do more with the iOS app
✨ Import chord progressions from AI (just copy & paste)
Analyze your progression with color-coded theory (Tonic, Subdominant, Dominant)
Use substitute, advanced & borrowed chord suggestions
Manage song structure with Section Mode
MIDI / Audio export
Advanced chords: slash chords, tensions & more
View Pro Plans

✨ AI Import on iOS App

Import chord progressions from AI — just copy & paste. Play with grooves, analyze Roman numerals, export MIDI.

Download on App Store
Synth/ Pulse
120
BPM

What is the Chord Progression Builder?

OtoTheory's Chord Progression Builder is a free online tool that lets you create, edit, and play chord progressions in real time. Choose from over 50 preset progressions, select from 15 groove patterns across 5 musical categories, and hear your ideas instantly — no downloads or sign-ups required. Built for guitar, bass, keyboard players, and DAW users who want to sketch musical ideas quickly.

Key Features

Who is it for?

Paste Chords from AI

OtoTheory is the fastest way to hear chord progressions generated by AI. Copy the output from ChatGPT, Claude, or Gemini — paste it into the builder — and press play. The parser automatically recognizes chord names, section labels like [Verse] and [Chorus], and various notation formats including pipe-separated bars.

Share Your Progressions

Every chord progression you create can be shared as a URL. Post it on Reddit, X (Twitter), or send it to a bandmate — they'll hear your exact progression when they open the link. No account or sign-up required.

Want the full experience? Get the iOS app for MIDI/audio export, unlimited saves, iCloud sync, and more.