B♭ Diminished 7th
B♭dim7
Notes
B♭ · D♭ · F♭ · A♭♭
Intervals
- RootB♭ (1P)
- Minor 3rdD♭ (3m)
- Diminished 5thF♭ (5d)
- Diminished 7thA♭♭ (7d)
Fretboard
On the fretboard, E represents F♭, and G represents A♭♭.
Adjust labels, frets, and palette in the interactive view.
Voicings & shapes
Drop-3 voicings (8)
Shell voicings (2)
Dim7 symmetrical (3)
One shape moved up 3 frets gives the next enharmonic root: C, E♭, G♭, and A dim7 are the same four notes.
About
The B♭ fully diminished 7 (B♭–D♭–F♭–A♭♭) stacks four minor thirds, giving it a fully symmetrical structure. Each note can be respelled as a root — B♭°7 is enharmonically the same chord as D♭°7, F♭°7, and A♭♭°7 — meaning a single shape on the guitar can function as four different leading-tone chords depending on context. This flexibility makes dim7 especially useful as a passing or substitution chord, often resolving up a half step (here to C♭). All four tones carry the chord’s identity; the chord is defined by its symmetry, so removing any note weakens that quality. On guitar, one shape repeats identically every three frets. Compared to B♭m7♭5, dim7 is more unstable and dramatically tense.
Chord diagrams
Bb Diminished 7th voicing charts — tap a sheet to open it full size to save or print.
Similar chords
Chords sharing two or more notes with this one, ranked by overlap.
Scales containing this chord
- B♭ Diminished (deg 1)
- A♭ Diminished (deg 2)
- A♭ Harmonic Minor (II)
- B Diminished (deg 8)
- B Harmonic Minor (VII)
- D Diminished (deg 6)
- D Harmonic Minor (VI)
- D♭ Diminished (deg 7)
- E Diminished (deg 5)
- F Diminished (deg 4)
- F Harmonic Minor (IV)
- G Diminished (deg 3)
Scales whose notes include every chord tone. The Roman numeral (or scale degree) marks the chord root’s position in the scale.