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New Released in April 2026

A Flat Diminished Chord on Guitar (Abdim)

To play Abdim on guitar, press the strings shown below; some strings ring open. Then strum all six strings: the notes Ab, Cb, Ebb ring together. First the picture, then each finger, then three chords to practise Abdim with.

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  • MIDI keyboard
  • Digital or acoustic piano
  • Guitar
  • Computer, phone or tablet
4fr××
Abdim Ab Cb Ebb

The A flat diminished guitar chord, finger by finger

4fr××
Abdim Ab Cb Ebb

Finger by finger

  • Middle: 6th string (low E), fret 4
  • Little: 4th string (D), fret 6
  • Ring: 3rd string (G), fret 4
  • Index: 2nd string (B), fret 3

Strings to play

4x643x: × = do not play, 0 = open string.

Where Abdim is used

Abdim wants to move up one fret: play Abdim, then A or Am, and it resolves.

Abdim string by string

6th string (low E)fret 4: Ab
4th string (D)fret 6: Ab
3rd string (G)fret 4: Cb
2nd string (B)fret 3: Ebb

Slide this shape along the neck: fret 2 = F#dim, fret 3 = Gdim, fret 5 = Adim, fret 6 = Bbdim.

A short Abdim routine

  1. Put the shape down slowly and pick each string once to check it rings.
  2. Lift the hand, then land all fingers together. Repeat ten times.
  3. Switch between Abdim and Ab for one minute, then try Db.

Play Abdim with these chords

Pick any two of these and switch back and forth: they all fit with Abdim.

Ab · Db · Eb

ChordRunner on a phone next to an acoustic guitar, with a chord block on screen

Play Abdim in a game

Abdim turns up between other chords in ChordRunner; strum it on time and the runner jumps. MIDI keyboard or microphone, both work. MIDI keyboard or microphone, both work.

Play the demo

Abdim on piano · Easy guitar chords · Guitar chord game

Common questions

What notes are in the Abdim guitar chord?

A flat diminished has three notes: Ab, Cb, Ebb. On the guitar some of them are doubled on different strings, so all six (or five) strings sound like one chord.

Which fingers do I use for Abdim?

Middle finger: 6th string (low E), fret 4, little finger: 4th string (D), fret 6, ring finger: 3rd string (G), fret 4, index finger: 2nd string (B), fret 3.

Can I practise Abdim with a microphone or MIDI keyboard?

Both work in ChordRunner. The microphone hears an acoustic or electric guitar; a USB MIDI keyboard is detected automatically. Either way Ab, Cb, Ebb must sound together.

Your instrument is the controller.

ChordRunner is a browser game that teaches piano and guitar chords: a chord appears on screen, you play it on a real instrument, and your runner jumps. MIDI keyboard or microphone, both work.

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