Adim7 Guitar Chord
Adim7 is a four-note fully diminished seventh chord built from A, C, D#, F#. Its symmetrical structure — four notes each a minor third apart — creates maximum harmonic tension and tonal ambiguity. It is a powerful tool for dramatic resolutions in jazz, classical, and film scoring.
4 ways to play Adim7
Notes
Intervals
A (Root), C (Minor 3rd), D# (Diminished 5th), F# (Diminished 7th)
Found in keys
Notes in the A Diminished 7th Chord
The A Diminished 7th chord is built from 4 notes: A, C, D#, F#. It is a diminished 7th chord — built from a root, minor third, diminished fifth, and diminished seventh (9 semitones above the root). On guitar, these notes are voiced across multiple strings simultaneously to create the full chord sound. Depending on the voicing, some notes may be doubled in different octaves to fill out the sound.
Keys That Contain A Diminished 7th
Adim7 shares its leading-tone function with the Adim chord, which is the vii° in these keys:
Common Chord Progressions with Adim7
A Diminished 7th appears in many common progressions. Here are the most-used patterns when Adim7 is the tonic chord:
Use our chords in a key tool to find all the chords that naturally pair with Adim7 in any key.
Frequently Asked Questions
What notes are in the A Diminished 7th chord?
The A Diminished 7th chord is made up of A, C, D#, F#. These 4 notes form a four-note chord structure.
What key is the A Diminished 7th chord in?
A Diminished 7th naturally appears in the keys of Bb Major. It can also appear in other contexts as a borrowed chord or secondary chord.
How do I play the Adim7 chord on guitar?
Place your fingers on the guitar fretboard according to the diagram above. The numbered dots show finger placement (1 = index, 2 = middle, 3 = ring, 4 = pinky), "O" means play the string open, and "X" means mute that string.
Other A Chords
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