A Diminished Chord

Adim Level 5: The Abyss

A Diminished (Adim) is built from the notes A, C, Eb. Its intervals are Root — Minor 3rd — Diminished 5th. Tense, compressed, and unstable. The diminished triad sounds like it needs to go somewhere — it creates a feeling of suspense, anxiety, or unresolved drama.

Hear A Diminished Chord

Piano sample · tap to play

Notes and intervals

Interval Semitones Note
Root 0 A
Minor 3rd 3 C
Diminished 5th 6 Eb

What does a diminished chord sound like?

Tense, compressed, and unstable. The diminished triad sounds like it needs to go somewhere — it creates a feeling of suspense, anxiety, or unresolved drama.

A Diminished Chord in music

A tense chord used as vii° in Bb major. A diminished creates a strong pull toward Bb that classical and jazz composers use for dramatic effect.

How to recognise a diminished chord by ear

Diminished sounds "squeezed." Both intervals are minor thirds, creating a tight, symmetrical structure. If a chord makes you feel uneasy or tense — like something is about to happen — that's diminished.

Practice identifying this chord in ChordFrog's Level 5: The Abyss .

Practice tip

A diminished is vii° in Bb major, a common jazz and wind-instrument key. Play Bb major → A diminished → Bb major to hear the leading-tone resolution. The A-Eb tritone within A diminished creates the pull that makes this resolution so strong.

Frequently asked questions

What notes are in a A Diminished chord?
A Diminished (Adim) contains three notes: A, C, Eb. The intervals are Root, Minor 3rd, Diminished 5th.
How do I recognise A Diminished by ear?
Diminished sounds "squeezed." Both intervals are minor thirds, creating a tight, symmetrical structure. If a chord makes you feel uneasy or tense — like something is about to happen — that's diminished. Practice identifying A Diminished in ChordFrog's Level 5 (The Abyss).
What level is A Diminished in ChordFrog?
A Diminished is introduced at Level 5: The Abyss. This is the final level, adding diminished and augmented triads for the complete chord vocabulary.

Other A chords

A Major Chord A Minor Chord A Augmented Chord A Sus2 Chord A Sus4 Chord

All Diminished Chords chords

C Diminished Chord D♭ Diminished Chord D Diminished Chord E♭ Diminished Chord E Diminished Chord F Diminished Chord F♯ Diminished Chord G Diminished Chord A♭ Diminished Chord B♭ Diminished Chord B Diminished Chord

Hear a diminished chord for yourself

Train your ear to recognise this chord instantly with ChordFrog's progressive levels.

Coming soon

Requires iOS 16 or later.