Bdim Guitar Chord (B Diminished)

Q: What notes are in the Bdim chord?

Bdim has 3 notes: B, D and F . Its formula is 1 – ♭3 – ♭5: B is the root, D a minor 3rd and F a diminished 5th above it.

Q: How do you play Bdim on guitar?

The shape in the main diagram is x20x01 (open position). Put your ring finger (3) on the 2nd fret of the A (5th) string. Put your middle finger (2) on the 1st fret of the high E (1st) string. Let the D (4th) and B (2nd) strings ring open (marked O). Don't play the low E (6th) or G (3rd) strings (marked X). Strum from the A (5th) string down (4 strings).

The Bdim guitar chord (B diminished) has 3 notes: B, D and F. Below you'll find 5 shapes with diagrams, how to play it step by step, the keys it belongs to and common progressions that use it.

x20x01 · open position

Notes: B – D – F
Formula: 1 – ♭3 – ♭5
Type: diminished
Difficulty: easy

Transpose a song

All 5 ways to play Bdim on guitar

x20x01 open position
x20401 open position
x2343x at the 2nd fret
75x76x at the 5th fret
x-x-9-10-x-10 at the 9th fret

Diagrams: strings run from the lowest on the left; X = don't play, O = open string, numbers = fingers (1 index, 2 middle, 3 ring, 4 little finger).

How to play Bdim on guitar

Main shape: x20x01 (open position).

Put your ring finger (3) on the 2nd fret of the A (5th) string.
Put your middle finger (2) on the 1st fret of the high E (1st) string.
Let the D (4th) and B (2nd) strings ring open (marked O).
Don't play the low E (6th) or G (3rd) strings (marked X).
Strum from the A (5th) string down (4 strings).

Bdim notes and intervals

Note	Formula	Interval from the root
B	1	root
D	♭3	minor 3rd
F	♭5	diminished 5th

Inversions: the same notes with another one in the bass, written as slash chords: Bdim/D (1st inversion) and Bdim/F (2nd inversion).

Bdim on piano and ukulele

Bdim on piano B – D – F
Bdim on ukulele 4212

Which keys use Bdim?

Bdim is one of the basic chords of 2 keys. Its number (Roman numeral) and job change with the key:

Key	Written	Numeral	Function
C major	B°	vii°	dominant
A minor	B°	ii°	predominant
C minor	B°	vii°	dominant (harmonic minor)

Transpose Bdim

Move the chord up or down by semitones to see its name and notes in another key.

Bdim B D F original

Diminished chords on every root: F♯dim Gdim A♭dim Adim B♭dim Bdim Cdim C♯dim Ddim E♭dim Edim Fdim

Frequently asked questions

What notes are in the Bdim chord?

Bdim has 3 notes: B, D and F. Its formula is 1 – ♭3 – ♭5: B is the root, D a minor 3rd and F a diminished 5th above it.

What is a diminished chord?

A diminished chord has a root, a minor 3rd and a diminished 5th (1–♭3–♭5). It is written dim or °. In a major key, the chord on the 7th note (vii°) is diminished.

How many ways can you play Bdim on guitar?

This page shows 5 shapes: x20x01 (open position), x20401 (open position), x2343x (at the 2nd fret), 75x76x (at the 5th fret) and x-x-9-10-x-10 (at the 9th fret). All of them contain the chord's essential notes.

How do you play Bdim on guitar?

The shape in the main diagram is x20x01 (open position).

Put your ring finger (3) on the 2nd fret of the A (5th) string.
Put your middle finger (2) on the 1st fret of the high E (1st) string.
Let the D (4th) and B (2nd) strings ring open (marked O).
Don't play the low E (6th) or G (3rd) strings (marked X).
Strum from the A (5th) string down (4 strings).

Is there an easy way to play Bdim?

Bdim is already one of the easier chords. The easiest shape is x20x01 (open position).

What key is Bdim in?

Bdim is vii° in C major and ii° in A minor. It is also vii° in C minor (harmonic minor, with the raised 7th). The other chords of C major are C, Dm, Em, F, G and Am.

More chords

Last updated: October 12, 2026