The Bdim chord
The Bdim chord is a passing chord that needs to move. Its notes (B - D - F) form a diminished triad, which is why it shows up across early jazz and the Great American Songbook. Songwriters pick the Bdim when they want a passing tension between two stable chords, and on guitar it sits near the nut for most common keys. The vii chord in C major, and a turnaround colour in jazz standards. The voicings, theory, progressions and song references that follow are organised so you can skim once or settle in for the full picture.
Hear the Bdim in the chord builder →Voicings for Bdim
Common ways to grip the Bdim on guitar and piano. Guitar diagrams read low E to high E left-to-right; an × means muted, an open circle above the nut means an open string. Filled dots are fretted notes.
Guitar , full chord shapes
CAGED-derived voicings for Bdim across the neck. Pick the shape closest to where your hand already sits.
Guitar , triad shapes
Three-note voicings on three adjacent strings. Light textures for arpeggios, pop layering and chord-melody work.
Piano voicings
Root position and inversions. The bass note matters: each inversion changes how the chord sits under a melody.
The theory behind Bdim
Progressions that use Bdim
Short progressions that put the Bdim to work. Each one is shown in a different key so you can pick the one that suits your singer.
This chord appears as a borrowed or passing chord in many minor-key progressions.
→ Build this in the chord builderSongs that feature Bdim
Real records where this chord does structural work. No lyrics quoted, just the title and artist so you can pull up a copy and hear it in context.
- Misty by Erroll Garner. Bdim as a passing chord.
- Autumn Leaves by Standard. Bdim within the standard's changes.
- All of Me by Standard. Bdim as a transition chord.
Related chords
Chords a step away from the Bdim in the songwriting circle, the natural neighbours when you want a substitution.
Keys where Bdim lives
The keys where this chord turns up diatonically. Open any key page for the full set of progressions that lean on it.
More songwriting tools
Got the chord but still wrestling with the lyric? Find the right rhyme in RhymeForge, or break a writer's block with the unexpected word-pair generator in CollisionLab. Need to map a full progression? The chord builder on the home page is where the Bdim fits into context. All free, no signup.
About the chord builder
The Undercover Zest chord progression builder is a free interactive tool that maps every diatonic and borrowed chord in every key. Click a Roman numeral to hear it, drag chords into a progression, then audition voicings, inversions and tensions until the song clicks.
This page is a static reference for the Bdim. For interactive playback, voice-leading hints and substitution suggestions, open the chord builder above.