A♯ Diminished 7th
Also Known As
Hear the A♯ Diminished 7th chord played for you.
A♯°7
A♯ – C♯ – E – G
Formula:R-m3-d5-d7
Intervals:P1-m3-d5-d7
Scale Degrees:1-b3-b5-bb7
Introduction
The A♯ Diminished 7th chord is a four-note chord made up of A♯, C♯, E, and G. It is built from a root, minor third, diminished fifth, and diminished seventh.
The A# Diminished 7th piano chord (A#dim7) consists of the notes A#, C#, E, G. It is built by stacking three minor thirds, creating a fully symmetrical 4-note chord, giving it a extremely tense and dramatic character, fully symmetrical and harmonically versatile. Formula: R-m3-d5-d7 | Scale degrees: 1-b3-b5-bb7.
Notes
A♯ Diminished 7th Inversions
| Position | Notes |
|---|---|
| Root Position | A♯ – C♯ – E – G |
| 1st Inversion | C♯ – E – G – A♯ |
| 2nd Inversion | E – G – A♯ – C♯ |
| 3rd Inversion | A♯ – C♯ – E – G |
Key Signature
The key of A# Diminished 7th (enharmonically equivalent to Bb Diminished 7th) has 2 flats.
B♭E♭
Order of flats
Flats are added in a fixed order — the reverse of the sharp order. Each new flat key adds the next flat on the list.
B♭E♭A♭D♭G♭C♭F♭
Mnemonic: Battle Ends And Down Goes Charles’ Father
Chords in the Key of A♯ Major
These are the diatonic triads built on each degree of the A♯ major scale:
C
D
E
F
G
A
B
C
D
E
F
G
A
B
I — A♯ Major (major)
Theory: Intervals
Formula: R-m3-d5-d7
Intervals: P1-m3-d5-d7
The A♯ Diminished 7th is built by stacking intervals from the root note. The formula R-m3-d5-d7 describes the scale degrees used. The intervals P1-m3-d5-d7 show the distance between each note in the chord.
A♯ Diminished 7th — Frequently Asked Questions
What notes are in the A# Diminished 7th chord?
A# Diminished 7th is built from the A# root. Check the interactive keyboard above for exact notes and fingering.
How is the A# Diminished 7th chord used in music?
A# Diminished 7th appears in jazz, pop, and classical contexts. Its sound depends on the chord quality (Diminished 7th).
What is the fingering for A# Diminished 7th?
See the fingering chart above. Right hand typically uses thumb on root. Left hand uses pinky on root.
What are the inversions of A# Diminished 7th?
Use the inversion buttons above to see each inversion with notes, fingering, and staff notation.
Practice Tips
- Symmetrical — only 3 unique dim7 chords.
- Pivot chord for modulation.
- Maximum dramatic tension.
- Classical cadence chord.
- Compare with A#m7b5.
- Film scoring suspense.
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.