Add a chord to see what typically follows it in real music
Build a progression of 3+ chords to find matching songs
Your explored progressions will appear here
Every songwriter, producer, and musician has encountered the question: “What chord should come next?” Tools like Hooktheory’s Trends database have shown that chord progressions in real music follow predictable statistical patterns. But those tools are behind paywalls or require signup. Chord Cascade brings this insight to everyone — free, open, and instantly accessible.
An interactive chord progression probability explorer. Build chord progressions using Roman numeral analysis, and instantly see which chords statistically tend to follow — based on patterns distilled from analysis of thousands of popular songs. Discover famous songs that use your progression, hear it played back with synthesized audio, and explore common progressions across genres.
Under the hood, Chord Cascade uses a weighted transition matrix derived from music theory research — including Markov chain analysis of chord progressions, the Hooktheory TheoryTab database patterns, and the Chordonomicon dataset of 680,000 songs. Each chord has weighted probabilities for what typically follows it. The system normalizes these probabilities and displays the most likely next chords with visual indicators. Audio playback uses the Web Audio API with FM synthesis to create warm, piano-like tones.