Paste your chord progression into the Key Finder. It analyzes the chords and ranks likely keys with fit scores. The top match shows the full Roman numeral analysis so you can confirm the key makes harmonic sense.
What if my progression fits multiple keys?
Many progressions fit multiple keys. The tool ranks all possibilities by fit score and highlights distinguishing chords (chords that only appear in one of the candidate keys) to help you determine the true key.
Does the Key Finder work with slash chords?
Yes, the Key Finder handles slash chords, inversions, and extended chords. It uses the full chord quality to determine key fit, not just the root notes.
Page detail levelSimple keeps pages short: extra theory and advanced controls stay tucked away until you open them. Everything shows every section and control at once.