A♯dim7 chord on guitar

A♯dim7 is A♯, C♯, E and G. The easiest shape is x-1-2-0-2-0. Tap Play, then slow it down.

x-1-2-0-2-0 · open · easy

Notes: A♯ · C♯ · E · G
Formula: 1 · ♭3 · ♭5 · ♭♭7
First shape: x-1-2-0-2-0

How to play A♯dim7 on guitar

Shape 1, x-1-2-0-2-0, reading from the low E string on the left:

A♯: index finger, 1st fret of the A string.
E: middle finger, 2nd fret of the D string.
C♯: ring finger, 2nd fret of the B string.
Leave the G and high E strings open: G and E.
Strum from the A string down; the low E string stays silent.

If an open string sounds dead, a fingertip is leaning on it. Come down more on the tips, with your knuckles bent.

Other ways to play A♯dim7

6-x-5-6-5-x: movable shape at the 5th fret, medium. The root is on the low E string, so you can slide this shape to play any diminished seventh chord.
x-13-14-12-14-x: movable shape at the 12th fret, medium. This is the open Adim7 shape with a barre behind it, root on the 5th string.
x-x-8-9-8-9: movable shape at the 8th fret, medium. Fewer strings, so it sounds lighter and is quicker to change to.

A♯dim7 chord changes

The chords A♯dim7 usually goes to, and what changes under your fingers.

B (leads up a half step): A♯dim7 (x-1-2-0-2-0) to B (x-2-4-4-4-2): the index finger lays across the A to high E strings at the 2nd fret, your middle finger lands on the D string, 4th fret, the ring finger goes to the G string, 4th fret, the pinky finger comes down on the B string, 4th fret. Nothing carries over, so drill it slowly, lifting and landing all fingers at once. B on guitar
Bm (leads up a half step): A♯dim7 (x-1-2-0-2-0) to Bm (x-2-4-4-3-2): the index finger lays across the A to high E strings at the 2nd fret, your middle finger lands on the B string, 3rd fret, the ring finger goes to the D string, 4th fret, the pinky finger comes down on the G string, 4th fret. No finger can stay, so practice lifting all of them together and landing the new shape as a unit. Bm on guitar
E♭ (a fifth down): A♯dim7 (x-1-2-0-2-0) to E♭ (x-x-1-3-4-3): the index finger slides across to the D string at the same fret, move the middle finger to the G string, 3rd fret, the ring finger goes to the high E string, 3rd fret, the pinky finger comes down on the B string, 4th fret. No finger can stay, so practice lifting all of them together and landing the new shape as a unit. A♯ and G carry over from one chord to the other. E♭ on guitar

A♯dim7 is a diminished seventh: three minor thirds stacked, so the chord divides the octave into four equal parts. A♯dim7 can stand in for a dominant seventh a half step below, which is why it links chords so smoothly. On guitar you hear it best picked slowly, string by string.

Practice A♯dim7 in two minutes

Pick shape 1 one string at a time, low to high: A♯, E, G, C♯, E. Every note should ring clearly; if one thuds, adjust that finger before you strum. Next, alternate x-1-2-0-2-0 and 6-x-5-6-5-x, slowly, until the change takes less than a beat.

Written B♭dim7, it's the same chord with the same frets.

Keys and progressions with A♯dim7

A♯dim7 on piano and ukulele

A♯dim7 on piano and ukulele uses the same 4 notes in a different layout. See all three together.

Related A♯ chords on guitar

Other diminished seventh chords

A♯dim7 on guitar: questions

What notes are in A♯dim7 on guitar?

A♯, C♯, E and G. In the x-1-2-0-2-0 shape the strings play A♯ (A string), E (D string), G (G string, open), C♯ (B string) and E (high E string, open), so E is doubled.

What's the easiest way to play A♯dim7 on guitar?

x-1-2-0-2-0, shape 1 above. Open strings do part of the work, so no barre.

Is A♯dim7 a barre chord on guitar?

Not in its common form: x-1-2-0-2-0 needs no barre.

Which string does A♯dim7 start on?

In the x-1-2-0-2-0 shape the lowest string you play is the A string at the 1st fret, which is A♯, the root. Skip the low E string.

Every shape above plays only A♯, C♯, E and G, checked by the site's tests. Updated September 2026.