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A♭ Diminished Major 7th

Diminished Major 7th · A♭ – C♭ – E♭♭ – G

The A♭ Diminished Major 7th chord (A♭dim(maj7)) contains the notes A♭, C♭, E♭♭, and G. Its interval formula is 1 ♭3 ♭5 7. A diminished triad with a major 7th — rare and unstable, used for chromatic color in jazz.

G♯ Diminished Major 7th
This is the same chord as G♯ Diminished Major 7th — the same keys on the keyboard, spelled with sharps.

At the keyboard

Ab · Cb · Ebb · G
Maintained by Justin Evans, a pianist of 25 years
Maintained for accuracy · Last updated July 2026 · How we review
Flashcards · Chord
Three questions on A♭ Diminished Major 7th
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A♭

The A♭ Diminished Major 7th chord is a four-note chord made up of A♭, C♭, E♭♭, and G.

Construction

A♭ Diminished Major 7th = Root + Minor 3rd + Diminished 5th + Major 7th = A♭ · C♭ · E♭♭ · G
NoteIntervalDegree
A♭Root1
C♭Minor 3rd♭3
E♭♭Diminished 5th♭5
GMajor 7th7

Key Signature

A Diminished Major 7th chord is built from symmetrical or ambiguous intervals, so it doesn’t belong to a single key and has no key signature of its own.

A♭ Diminished Major 7th — Frequently Asked Questions

What is the A♭ Diminished Major 7th chord on piano?
The A♭ Diminished Major 7th chord contains the notes A♭ – C♭ – E♭♭ – G. On piano, play these notes together to sound the chord.

Related Tools

Chord FinderLook up any chord — see the notes, hear it, and play along.Chord DrillTimed drills to build speed and recognition across all chord types.Practice RoomPlug in a MIDI keyboard and get real-time feedback on every chord and scale.Circle of FifthsVisualize key relationships, relative minors, and key signatures.MIDI MonitorLive MIDI message stream with note names, velocity, and a scrolling staff.

References & Further Reading

The note names, intervals, fingering, and harmony on this chord page are grounded in the following sources. Public domain treatises and scores are linked to their full text; primary data is piano.org's own interval-derived reference dataset — continuously maintained and human-verified, with no fixed publication date.

  1. 1

    Jadassohn, Salomon(1883)

    A Manual of Harmony

    Public domain treatise
  2. 2

    Prout, Ebenezer(1889)

    Harmony: Its Theory and Practice

    Public domain treatise
  3. 3

    Goetschius, Percy(1889)

    The Material Used in Musical Composition

    Public domain treatise
  4. 4

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Entry reviewed and maintained by Justin Evans. Corrections are read and applied.Report an error

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