Bdim Piano Chord

B diminished is the Bdim piano chord. It has three notes: B, D and F. All three are white keys, which makes it the only all white diminished chord on the keyboard.

1B3D5FC3C4

B at the bottom, then D and F. Right hand 1-3-5, left hand 5-3-1. Every key here is white.

How to play Bdim on piano, step by step

  1. Start on the B below middle C. That is the lowest note of the chord.
  2. Thumb (1): B
  3. Middle finger (3): D
  4. Little finger (5): F
  5. Press them together with the right hand. The left hand plays the same notes with fingers 5, 3, 1 an octave lower, or just B on its own as a bass note.

This chord is the vii of C major, which means it is built entirely from notes in the key of C. That is why it needs no black keys, and why it turns up so often in music in C.

Inversions of Bdim

The same 3 notes with a different one at the bottom. All of them are Bdim; which you play depends on what the hand is coming from. Tap any card to hear it.

First inversionD F B
Bdim piano chord diagram, first inversion, D F B
Lighter than root position and less final. A flat third in the bass tips the chord forward, which is why it usually sits between two other chords rather than at the end of a line.
Second inversionF B D
Bdim piano chord diagram, second inversion, F B D
Open and slightly unresolved. A fifth in the bass makes the chord sound like a step on the way somewhere, which is mostly how it is used.

If it sounds wrong

The chord sounds merely sad
Check the top note is F, not F sharp. F sharp gives B minor, which is sad; F gives B diminished, which is tense.
The chord sounds unbearable on its own
It is meant to be unstable. Play B diminished then C major and the tension resolves; a diminished chord is a doorway, not a room.
The notes are uneven
The gaps between the fingers are equal here, which makes the shape easy to balance. If one note is weak it is usually the little finger; lean the hand slightly outward.

What makes it a Bdim

B · D · F 1 ♭3 ♭5

B diminished is B, D and F: the root, the flat third and the flat fifth. Both gaps are minor thirds, three half steps each, which is what makes the shape symmetrical under the hand.

It is the vii chord of C major, the one built on the leading note. Every one of its notes wants to move by a half or whole step into a C chord, which is why it pulls upward so strongly.

Bdim vs Bm

The top note. B minor has F sharp; B diminished lowers it to F. That single key is the difference between a chord that can sit still and one that cannot.

B minor belongs to the key of D; B diminished belongs to the key of C, where it works as the chord immediately before home.

Questions about Bdim

Which notes are in a Bdim chord on piano?

B, D and F. It is a minor chord with the fifth lowered by one key.

What is the difference between Bdim and B minor?

The top note. B minor has a normal fifth; Bdim lowers it by one key to F. That single change turns a sad chord into a tense one.

How does a diminished chord resolve?

Usually up by one key. Bdim leans toward C major, and playing the two in a row is the quickest way to hear why: every note of the diminished chord is a half step or a whole step from where it wants to go.

Is Bdim hard to play?

No. It is three notes with an even shape, since a diminished triad is two minor thirds stacked. The intervals are the same size, which makes the hand position symmetrical and easy to remember.

Chords to learn next

Other B chords