A# Half Diminished

Notes:A# – C# – E – G#
Formula:R-m3-d5-m7
Intervals:P1-m3-d5-m7
Scale Degrees:1-b3-b5-b7

Introduction

The A# Half Diminished piano chord (A#m7b5) consists of the notes A#, C#, E, G#. It is a diminished triad with an added minor 7th, giving it a dark, moody, and tense character commonly used in jazz and minor key progressions. Formula: R-m3-d5-m7 | Scale degrees: 1-b3-b5-b7.

Enharmonic equivalent: Aβ™― is enharmonically equivalent to Bβ™­. See Bb Half Diminished.

Notes

Notes:A# – C# – E – G#

A# Half Diminished Inversions

PositionNotes
Root PositionA#4 – C#5 – E5 – G#5
1st InversionC#5 – E5 – G#5 – A#5
2nd InversionE5 – G#5 – A#5 – C#6
3rd InversionA#4 – C#5 – E5 – G#4

Key Signature

The key of A# Half Diminished has Key signature data not available.

Theory: Intervals

Formula: R-m3-d5-m7
Intervals: P1-m3-d5-m7

The A# Half Diminished is built by stacking intervals from the root note. The formula R-m3-d5-m7 describes the scale degrees used. The intervals P1-m3-d5-m7 show the distance between each note in the chord.

A# Half Diminished β€” Frequently Asked Questions

What notes are in the A# Half Diminished chord?

A# Half Diminished is built from the A# root. Check the interactive keyboard above for exact notes and fingering.

How is the A# Half Diminished chord used in music?

A# Half Diminished appears in jazz, pop, and classical contexts. Its sound depends on the chord quality (Half Diminished).

What is the fingering for A# Half Diminished?

See the fingering chart above. Right hand typically uses thumb on root. Left hand uses pinky on root.

What are the inversions of A# Half Diminished?

Use the inversion buttons above to see each inversion with notes, fingering, and staff notation.

What is the ii-V-i progression with A# Half Diminished?

A# Half Diminished functions as the ii chord in minor-key jazz harmony, resolving through the V7 to the minor tonic.

Practice Tips

  • Minor-key ii–V–i is essential jazz vocabulary.
  • Compare with A#dim7 and A#m7.
  • The flatted fifth creates the half-diminished tension.
  • Essential for jazz minor keys.
  • The ΓΈ symbol means half-diminished.
  • Practice in context of minor-key progressions.