B diminished
How to play Bdim — Diminished
Bdim (Diminished)B · D · F
Guitar samples: Acoustic guitar — University of Iowa (via tonejs-instruments, CC-BY 3.0)
B diminished — notes and structure
The Bdim chord stacks minor thirds up to the flattened fifth — tense and unstable, wanting to resolve.
The Bdim diminished consists of the notes B, D, F. Its interval structure is R–3–5 — the root, then each chord tone stacked above it. This is the same chord you see in the interactive finder above, drawn on the guitar fretboard with the root circled and every chord tone labelled.
Bdim stacks a minor third (D) and a diminished fifth (F) above the root B.
The finder shows 2 ways to play Bdim — an open-position shape reaching up to the 4th fret. None of them need a barre.
What key is Bdim in?
Every note of Bdim belongs to the scales below, so the chord sounds at home in each of these keys — the roman numeral is the degree it sits on.
- C major — the vii° chord
- A minor — the ii° chord
Chords that go with Bdim
In C major, the chords built on the first, fourth and fifth degrees carry most songs — put Bdim next to these:
Frequently asked questions
- What notes are in the B diminished chord?
- The Bdim chord contains the notes B, D, F. It stacks minor thirds up to the flattened fifth — tense and unstable, wanting to resolve.
- How many ways can you play Bdim on guitar?
- 2 voicings are shown on this page — from open position up the neck — each with its own fingering diagram and audio.
- Is Bdim a hard chord to play?
- It is fairly beginner-friendly — there is an open-position shape and none of the voicings need a barre.
- What key does Bdim belong to?
- Bdim fits C major (where it is the vii° chord), A minor (where it is the ii° chord) — every note of the chord is in those scales.