Tools / Chords / A diminished

A diminished chord on guitar (Adim)

Also written Adim or A°

A diminished contains the notes A, C, and E♭. The open shape keeps the bass on A and leaves the two E strings muted.

Open×-0-1-2-1-×

Positions on the neck1 of 5

How it’s built

A1Root

C♭3Minor 3rd

E♭♭5Diminished 5th

Formula 1, ♭3, ♭5

Positions on the neck1 of 5

Inversions

The same three notes, with a different one in the bass.

Root positionA–C–E♭AdimBass A

First inversionC–E♭–AAdim/CBass C

Second inversionE♭–A–CAdim/E♭Bass E♭

Why it sounds like that

A diminished is built from the formula 1, ♭3, ♭5, giving A, C, and E♭. The flattened fifth creates the chord's tense, unstable quality. Compare it to A minor, which raises the fifth to E.

What goes wrong with A diminished?

Letting the low E string ring out, which adds an E that is not part of A diminished.
Flattening the middle finger onto the G string, causing the 2nd fret note to buzz.
Strumming the high E string, which introduces an outside note.

When to use it

A diminished functions as the vii° chord in B♭ major, leading to B♭ major. It also works as a passing chord between A minor and B♭ major. Use it in blues or jazz for a tense, unresolved color.

Changing to and from A diminished

Move to A minor by lifting the ring finger from the G string's 2nd fret, leaving the 1st fret notes and open A string in place.

Which voicing to use

The open position is the easiest and keeps the root A in the bass. The 5th fret and 12th fret shapes repeat the same voicing an octave higher. The Adim/C inversions place C in the bass, softening the root emphasis.

How do you play an A diminished chord on guitar?

Open

Beginner● On the diagram

A diminished is played in open position as × 0 1 2 1 ×: index finger on the D string at fret 1, ring finger on the G string at fret 2 and middle finger on the B string at fret 1. The A string rings open. The low E and high e strings stay muted.

Tip — The open shape is beginner-friendly, but the two muted E strings require careful right-hand control to avoid accidental strums.

String-by-string breakdown

String	Fret	Finger	Note
6 (E)	muted	—	—
5 (A)	open	—	A (1)
4 (D)	1	1	E♭ (♭5)
3 (G)	2	3	A (1)
2 (B)	1	2	C (♭3)
1 (e)	muted	—	—

5th fret

Intermediate

A diminished is played at the 5th fret as 5 6 7 5 × ×: index finger on the low E string at fret 5, ring finger on the A string at fret 6, pinky finger on the D string at fret 7 and middle finger on the G string at fret 5. The B and high e strings stay muted.

String-by-string breakdown

String	Fret	Finger	Note
6 (E)	5	1	A (1)
5 (A)	6	3	E♭ (♭5)
4 (D)	7	4	A (1)
3 (G)	5	2	C (♭3)
2 (B)	muted	—	—
1 (e)	muted	—	—

12th fret

Intermediate

A diminished is played at the 12th fret as × 12 13 14 13 ×: index finger on the A string at fret 12, middle finger on the D string at fret 13, pinky finger on the G string at fret 14 and ring finger on the B string at fret 13. The low E and high e strings stay muted.

String-by-string breakdown

String	Fret	Finger	Note
6 (E)	muted	—	—
5 (A)	12	1	A (1)
4 (D)	13	2	E♭ (♭5)
3 (G)	14	4	A (1)
2 (B)	13	3	C (♭3)
1 (e)	muted	—	—

Adim/C inversion · fret 1

Intermediate

A diminished is played at the 1st fret as × 3 1 2 1 ×: pinky finger on the A string at fret 3, index finger on the D string at fret 1, ring finger on the G string at fret 2 and middle finger on the B string at fret 1. The low E and high e strings stay muted.

String-by-string breakdown

String	Fret	Finger	Note
6 (E)	muted	—	—
5 (A)	3	4	C (♭3)
4 (D)	1	1	E♭ (♭5)
3 (G)	2	3	A (1)
2 (B)	1	2	C (♭3)
1 (e)	muted	—	—

Adim/C inversion · fret 6

Intermediate

A diminished is played at the 6th fret as 8 6 7 8 × ×: ring finger on the low E string at fret 8, index finger on the A string at fret 6, middle finger on the D string at fret 7 and pinky finger on the G string at fret 8. The B and high e strings stay muted.

String-by-string breakdown

String	Fret	Finger	Note
6 (E)	8	3	C (♭3)
5 (A)	6	1	E♭ (♭5)
4 (D)	7	2	A (1)
3 (G)	8	4	E♭ (♭5)
2 (B)	muted	—	—
1 (e)	muted	—	—

Common questions

What is the difference between A diminished and A minor?

A diminished has a flattened fifth (E♭), while A minor has a perfect fifth (E). The diminished fifth creates a more dissonant, unstable sound.

Can I play A diminished as a barre chord?

The open shape uses no barre, but the 5th fret and 12th fret shapes are movable. Slide the 5th fret shape down two frets to get G diminished.

Why are the two E strings muted in the open shape?

The open E strings are not chord tones of A diminished. Muting them keeps the voicing clean and prevents an unwanted major second clash.

How is A diminished written?

A diminished is written as A° or Adim. The root is A, and the symbols are A° and Adim.

String

Fret

Finger

Note

6 (E)

muted

—

5 (A)

open

—

A (1)

4 (D)

E♭ (♭5)

3 (G)

A (1)

2 (B)

C (♭3)

1 (e)

muted

—

String

Fret

Finger

Note

6 (E)

A (1)

5 (A)

E♭ (♭5)

4 (D)

A (1)

3 (G)

C (♭3)

2 (B)

muted

—

1 (e)

muted

—

String

Fret

Finger

Note

6 (E)

muted

—

5 (A)

A (1)

4 (D)

E♭ (♭5)

3 (G)

A (1)

2 (B)

C (♭3)

1 (e)

muted

—

String

Fret

Finger

Note

6 (E)

muted

—

5 (A)

C (♭3)

4 (D)

E♭ (♭5)

3 (G)

A (1)

2 (B)

C (♭3)

1 (e)

muted

—

String

Fret

Finger

Note

6 (E)

C (♭3)

5 (A)

E♭ (♭5)

4 (D)

A (1)

3 (G)

E♭ (♭5)

2 (B)

muted

—

1 (e)

muted

—