B Diminished Guitar Chord | All You Need To Know

The B diminished chord is one of the first chord you're going to learn.
Unlike the other beginner chords, this one has a specific quality: it is diminished!
That means that B dim is a minor chord but with a diminished fifth (1, b3, b5), while the standard minor chords are formed with a perfect fifth (1, b3, 5).
This unique characteristic gives the B diminished chord an unstable sound, containing a tension that pushes you somewhere to be resolved.
This chord is also denoted in the following ways:
- B dim
- B°
- Bmb5 (unusual but you could encounter it in some books)
These 3 tones chord is the basis for more complex diminished chords:
- If you add a minor seventh, you'll obtain a Bm7b5 chord, which is 1, b3, b5 and b7
- If you add a diminished seventh, you'll get a B dim7 chord, composed of 1, b3, b5, and bb7
You can learn more about this topic on my diminished chords tutorial.
Notes of the B dim chord:
BDF
How to create the Diminished chord:
Interactive Tool To Explore The B Dim Chord
Explore the different shapes for the B dim chord with this tool:
Keys With The B Diminished Chord
The most common place in which you'll find the B diminished chord is the 7th degree of the C major key:
Key | I | ii | iii | IV | V | vi | vii |
---|---|---|---|---|---|---|---|
C | C | Dm | Em | F | G | Am | B dim |
Of course, B dim is also present in the relative minor key, A minor:
Key | i | ii | III | iv | v | VI | VII |
---|---|---|---|---|---|---|---|
A | Am | B dim | C | Dm | Em | F | G |
Scales To Play Over a B Diminished Chord
The b3 and b5 in this chord make the locrian scale a great match, even if the overall sound will be a bit dissonant.
Other great matches are:
- B Minor Blues Scale (the b5 is the Blue Note!)
- B Dorian #4 Scale
- B Whole Tone Scale
You can find a complete analysis of scales and chords relationship on my ebook Scales Over Chords | Learn How To Play The Right Scales Over Any Chord
How To Play The Bdim Chord
Chord boxes are sorted from the easiest to the hardest. Learn how to read chord diagrams.
If you have difficulties with bar chord shapes, check the Bar Chords Tips tutorial.
Find more shapes on my all guitar chords online library.
Position 1
Movable

Position 2
Movable

Position 3
Movable

Position 4
Movable

Position 5
Movable

Want a printable pdf?
Download
the Free Guitar Chords Chart Pdf
Play This Chord With Other Roots
C dim | D dim | E dim | F dim | G dim | A dim | B dim | C#dim | D#dim | F#dim | G#dim | A#dim
Chord tones in the B dim chord
This fretboard map shows you the tones in the chord all along the neck. You can play this chord by choosing some of the chord tones.