Play a chord. Understand why it works. Know what to play next.
A music theory tool built for guitarists who learn by playing.
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Mic audio stays on your device
Mic audio stays on your deviceAm7
NEXT IVmaj7Fmaj7ArootC3rdE5thG7th
NextIVmaj7Fmaj7ii7Dm7V7G7
Mic audio stays on your device01 · Tones
Play a chord.
Tap a chord shape and learn exactly what it is.
- RootThe note the chord is named after.
- 3rdMakes the chord major or minor.
- 5thAdds weight and stability.
- 7thAdds tension and pull.
- ExtensionAny other chord tone, such as a 2nd, 4th or 9th.
Cmaj7x32000
CrootE3rdG5thB7th
Cmaj7Root3rd5th7th
Am7vi7
ArootC3rdE5thG7th
Key
C majorA minorG major
Or hear this as A minor →02 · Key
Understand why it works.
See any key mapped across the entire fretboard.
Pick a key to refine next chords.
03 · Next
Know what to play next.
IVmaj7Fmaj7ON BOARD
Subdominant: common continuationii7Dm7
Supertonic: descending fifths motionV7G7
Dominant: sets up tonic returnHolding Am7 · solidHovering IVmaj7 Fmaj7 · dashed preview
Cmaj7x32000
G320033
Am7x02010
Dm7xx0211
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PrivacyPractice
Know Your Key
See how any major or minor key lays out across the whole neck, then test whether you can spot its notes yourself.
ExploreKnow the Fretboard
Learn all six strings, open strings to the 22nd fret, until you can name any note on sight.
Start quizName That Chord
Put a name to the shapes you find while playing, and learn why each one sounds the way it does.
Identify a chordFounding players
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