Bbdim7

Q: What notes are in the Bbdim7 chord?

The Bbdim7 chord (Bb Diminished 7th) contains: Bb, Db, Fb, G. Its interval structure is shown above in the Theory section.

Q: How do I build Bbdim7 on the keyboard?

Take the root and add the remaining chord tones following the interval formula. The highlight shows chord content, while the inversion control changes which chord tone is in the bass.

Q: Which keys is Bbdim7 found in?

The chord acts as a diatonic degree in several keys — they are marked on the circle of fifths in the "Harmonic context" block.

Q: What can I substitute for Bbdim7?

A substitution depends on harmonic function and voice leading, not only on shared tones. Computed options appear in the "Substitutions" block and should be checked in context.

Bb Diminished 7th

Octaves

Musical context

ChordBbdimTriad

ChordBbdim7Bb Diminished 7th

ArpeggioBb minorBroken triad

ScaleBb minor7 notes

KeyBb minorMinor key

ProgressionAndalusianSequence

How the chord relates to the scale, mode, key and progression.

Theory

General info

Full name: Bb Diminished 7th
Symbol: Bbdim7
Root: Bb
Quality: Diminished 7th

Chord notes

1Bbroot

b3Dbminor 3rd

b5Fbdim 5th

bb7Gdim 7th

Functions & resolutions

Typical function in key: iiSubdominant (ii)Ab major
Stability / tension: Maximum tension — extremely unstable
Most common resolutions: BB Major DD Major
Unstable degrees: 2C
b3Db
resolves down to the 2nd
4Eb
b5E
resolves inward to the 4th
b6Gb
bb7G
resolves down to the tonic 5th
Main resolution: Bbdim7source
BB Major
Diminished Bbdim acts as a leading-tone chord — resolves up a half step to B. All tones are unstable, moving by semitones inward and outward to stable degrees.
Other resolutions: Bbdim7source
Deceptive resolution
DD Major
Due to its symmetry, a diminished 7th chord can resolve to any major or minor chord a minor 3rd apart.
Bbdim7source
Modal resolution
CmC Minor
In modal context, a diminished chord can be used as a passing chord, connecting two diatonic chords through chromatic bass motion.
Bbdim7source
Jazz reharmonization
A7A Dominant 7
In jazz, dim7 is often reinterpreted as a rootless dominant 7b9. For example, Bbdim7 ≈ A7b9, opening additional resolution paths.
Bbdim7source
Functional resolution
FmF Minor
A diminished chord can function as a leading-tone chord to any degree — not just the tonic. Often used before the ii, iii, or vi degrees.

Features

Character: Fully diminished, symmetric and unstable
Characteristic interval: Diminished 7th (°7)
Description: Four tones are stacked in minor 3rds; the diminished 5th and 7th create two tritones. Symmetry allows any tone to be enharmonically reinterpreted as the root.
Application: Leading-tone seventh in minor
Secondary leading-tone chords
Chromatic voice leading

Voicing & structure

Root position

v1Bb(Bb4)Bass

root

v2Db(Db5)m3from Bb

v3Fb(Fb5)m3from Db

v4G(G5)m3from Fb

Harmony

Compatible scales

All chord tones are contained in these scales — use them for improvisation.

ScaleC# Romanian minor ScaleC# Ukrainian Dorian ScaleE Romanian minor ScaleE Ukrainian Dorian ScaleG Romanian minor ScaleG Ukrainian Dorian ScaleA# Romanian minor ScaleA# Ukrainian Dorian ScaleC Phrygian dominant ScaleD Harmonic minor

This chord on guitar 🎸

See how Bbdim7 looks on guitar.

Explore

Circle of fifths

Highlighted major keys contain this chord among their diatonic harmonies.

Relative key: GmG minor
Dominant: FF major
Subdominant: EbEb major
Key signature: 2 flats (Bb, Eb)

What to learn next

ScaleBb Chromatic scaleScale to improvise over this chord ChordBb DiminishedA nearby chord on the same root — compare the sound PracticeChord trainerLock the fingering into muscle memory ProgressionChord progressionsHow this chord works inside real progressions ChordBb Half-dim 7Another related chord to practise

Recommended for you

Bb DiminishedA chord that sounds close

Bb Half-dim 7A chord that sounds close

Bb Chromatic scaleA scale related to this chord

Bb Diminished scaleA scale related to this chord

Practice

Keyboard Trainer

Reinforce it in practice — play and name notes on the interactive keyboard.

Open Trainer

Test yourself

(Press any key to start)

What notes are in the Bbdim7 chord?

How do I build Bbdim7 on the keyboard?

Which keys is Bbdim7 found in?

What can I substitute for Bbdim7?