Bdim (diminished)

3-note diminished on BB, D, F.

Press to hear the chord strummed low to high.

A minor third stacked on a minor third — the fifth is flattened, giving an unstable, tense sound that wants to resolve.

The notes

Pitches taken from the first fingering below — click any note to open its frequency page.

Interval formula

DegreeNoteWhat it is
1Broot
♭3Dminor third
♭5Fflat fifth (diminished)

The formula reads in semitones above the root (B): 1, ♭3, ♭5. A voicing may leave a tone out — often the fifth — but never adds one from outside this set.

Guitar fingerings · 4

32
open position
1243
open position
5fr3142
from fret 5
9fr123
from fret 9

Ukulele fingerings · 4

4213
open position
4fr1243
from fret 4
5fr3141
from fret 5
8fr2431
from fret 8

Read a diagram top-down: the thick bar is the nut, dots are where to press (the number is which finger), means play the open string, means don't play it. A bar across strings is a barre.

Other B chords

dim (diminished) chords on every root