Bdim Guitar Chord
B Diminished · B–D–F
Bdim is the B diminished chord: B–D–F. Its sound is tense and unstable — stacked minor 3rds that work as dramatic passing chords.
You'll rarely sit on Bdim for a full bar — diminished chords are connectors. Classic uses: passing between the I and ii chords in Bb major, or substituting for the V7♭9 a half-step below. The symmetrical shape repeats every three frets, so one grip gives you four chords.
The most common way to play Bdim is the diminished grip at the 7th fret (7 x 9 10 x 10, low E string to high E string). Below you'll find 3 ways to play it across the neck, from open position to barre and shell voicings, with the theory behind the chord and the progressions it lives in.
How to Play Bdim: 3 Voicings
Frets are listed from the low E string to the high E string. x = don't play that string, 0 = open string.
Bdim Chord Theory
| Interval | R | ♭3 | ♭5 |
|---|---|---|---|
| Note | B | D | F |
Bdim is built from the B minor scale.
Bdim Chord FAQ
What notes are in the Bdim chord?
Bdim contains 3 notes: B (R), D (♭3), F (♭5). The interval formula for a diminished chord is R–♭3–♭5.
What is the easiest way to play Bdim on guitar?
Use the diminished grip at the 7th fret: 7 x 9 10 x 10 (frets listed from the low E string to the high E string, x = don't play that string). Bdim has no open-position shape in standard tuning, so this movable form is the standard starting point.
Is Bdim a major or minor chord?
Bdim is built on a minor triad (B–D–F) with the ♭5 added, so it behaves as a minor-family chord.
What keys use the Bdim chord?
Bdim appears diatonically in D major (as vi), A major (as ii), and G major (as iii) — plus it's the home chord (i) of B minor.
Related Chords
Hear yourself play Bdim
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