B♭dim7
Dim 7 · B♭ – D♭ – F♭ – G
- B♭R
- D♭m3
- F♭♭5
- G♭♭7
Guitar voicings
Piano
- Root
- Third / sus
- Fifth
- Sixth / seventh
- Extension
About the B♭dim7 chord
The B♭dim7 chord (Dim 7) is built from B♭ (the root), D♭ (a minor third), F♭ (a diminished fifth) and G (a major sixth). Diminished seventh chords are symmetrical and restless, handy for dramatic passing motion.