Song Key Finder
Enter the chords in a song to find its key. Shows the most likely key, Roman numeral analysis, confidence level and common progression names.
Select Chords Used
Click on chord buttons to analyze the key of your song.
How a Musical Key Finder Works
If you have a chord progression (e.g., C Major, F Major, G Major) but do not know what musical key you are playing in, a key finder tool reverses the process. It analyzes the specific notes within your chords and matches them against the 24 major and minor keys.
Knowing your song's key is critical for writing melodies, adding a bassline, communicating with other musicians, and figuring out which scales (like the pentatonic or diatonic scale) you can use to solo over the track.
Frequently Asked Questions
Can a key finder with chords detect multiple keys?
Yes, it is very common in music theory for a simple chord progression (like Am and C) to exist perfectly in multiple keys (such as C Major or G Major). Our chord key finder will list all possible matching keys, ranked by the highest statistical probability.
What does it mean if my chords do not fit any key?
If your chords contain notes outside of a traditional 7-note diatonic scale, you might be using 'borrowed chords' (modal mixture) or passing secondary dominants. While this breaks strict music theory rules, it often sounds great! The tool will highlight the closest matching key.
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Transpose any chord progression to a new key instantly. Enter your chords, choose how many semitones to shift and get capo suggestions for easier shapes.
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