Read left to right, 6th string to 1st: a number is a fret, 0 is an open string, x is a string you do not play.
- Index finger on the 1st fret of the A string (5th).
- Middle finger on the 2nd fret of the D string (4th).
- Ring finger on the 2nd fret of the B string (2nd).
- Little finger on the 3rd fret of the G string (3rd).
- Let the high E string ring open.
- Do not play the low E string: start the strum from the A string.
String by string
What each string does in this shape, and which note of the chord it sounds. This is what to listen for when you pluck them one at a time.
| String | Fret | Finger | Note | In the chord |
|---|---|---|---|---|
| 6th (low E) | not played | — | — | — |
| 5th (A) | fret 1 | index | B♭2 | root |
| 4th (D) | fret 2 | middle | F♭3 | flat fifth |
| 3rd (G) | fret 3 | little | B♭3 | root |
| 2nd (B) | fret 2 | ring | D♭4 | minor third |
| 1st (high E) | open | — | F♭4 | flat fifth |
One string at a time: a chord strummed into a microphone is several notes at once, and a single string is something the page can hear exactly. A string in tune but on the wrong fret, or deadened by the finger beside it, shows up here and not on a tuner. Tap a string to check it again.
2 other ways to play B♭dim
The same 3 notes, somewhere else on the neck. A different shape puts a different note on top, so each one colours the chord slightly differently — and one of them is usually nearer the chord you are coming from.
- x-x-8-9-11-9A shape at the 8th fret · four fingers
- xx8656A shape at the 5th fret · four fingers
Holding it cleanly
One string rings open next to fretted ones. Arch the fingers so they come down on their tips — a finger lying flat will deaden the open string beside it, and the chord loses a note without sounding obviously wrong.
The lowest string is left out, because its open note is not in the chord. Aim the strum to start below it, or let the tip of a fretting finger rest against the unwanted string to keep it quiet.
The notes in B♭dim
A diminished chord is built from the root (1), ♭3 and ♭5 of its root’s major scale. From B♭ that gives B♭ – D♭ – F♭ (E). Two minor thirds stacked: tense and unstable, a passing chord between two steadier ones.
The same root, other chords: B♭ major, B♭m, B♭7, B♭maj7, B♭m7, B♭sus2, B♭sus4, B♭aug.
Keys that use B♭dim
B♭dim is built from the notes of 2 keys. Each link is that key’s full set of guitar chords — the ones that sound right next to this one.
Frequently asked questions
What notes are in a B♭dim chord?
B♭ diminished is three notes: B♭ – D♭ – F♭ (E) — the root, ♭3 and ♭5 of the B♭ major scale. On guitar the shape x12320 sounds B♭2, F♭3, B♭3, D♭4 and F♭4, so some of those notes appear more than once.
What is the easiest way to play B♭dim on guitar?
The usual shape is x12320 — an open-position shape, with four fingers. It is already about as easy as this chord gets.
Is B♭dim the same chord as A♯dim?
Yes — on guitar they are the same frets and the same sound. B♭ and A♯ are two names for one pitch, and which name a songbook prints depends on the key: a piece in a sharp key writes A♯dim, a piece in a flat key writes B♭dim.
What is the difference between B♭dim and B♭m?
One note. B♭dim is B♭m with its fifth lowered a semitone, to F♭. That flattened fifth is a tritone above the root — the most unstable interval there is — which is why B♭dim never sounds like a place to stop.
What keys is B♭dim in?
B♭dim is one of the seven chords of B major (as vii°) and G♯ minor (as ii°).