The F Diminished 7th chord is a four-note chord made up of F, A♭, C♭, and E♭♭. It is built from a root, minor third, diminished fifth, and diminished seventh.
Construction
F Diminished 7th = Root + Minor 3rd + Diminished 5th + Major 6th = F · A♭ · C♭ · E♭♭
| Note | Interval | Degree |
|---|---|---|
| F | Root | 1 |
| A♭ | Minor 3rd | ♭3 |
| C♭ | Diminished 5th | ♭5 |
| E♭♭ | Major 6th | 6 |
F Diminished 7th Inversions
| Position | Notes |
|---|---|
| Root Position | F – A♭ – C♭ – E♭♭ |
| 1st Inversion | A♭ – C♭ – E♭♭ – F |
| 2nd Inversion | C♭ – E♭♭ – F – A♭ |
| 3rd Inversion | E♭♭ – F – A♭ – C♭ |
Key Signature
A Diminished 7th chord is built from symmetrical or ambiguous intervals, so it doesn’t belong to a single key and has no key signature of its own.
Same Notes, Other Names
The notes F – A♭ – C♭ – E♭♭ aren’t exclusive to this chord. Depending on which note is the bass and how the chord functions, the same pitches also spell the following:
F Diminished 7th — Frequently Asked Questions
What is the F Diminished 7th chord on piano?
The F Diminished 7th chord contains the notes F – A♭ – C♭ – E♭♭. On piano, play these notes together to sound the chord.
What notes are in the F Diminished 7th chord?
The F Diminished 7th chord (Fdim7) contains four notes: F (root), Ab (minor third), Cb (diminished fifth, enharmonically B), and Ebb (diminished seventh, enharmonically D). All four notes are spaced exactly 3 semitones apart.
How does F Diminished 7th differ from F Diminished?
F Diminished is a three-note triad (F, Ab, Cb). F Diminished 7th adds Ebb/D as the diminished seventh, completing the symmetrical four-note structure and increasing harmonic tension.
Why is the Diminished 7th chord symmetrical?
Every note in Fdim7 is exactly 3 semitones from the next. Fdim7 contains the same pitches as Ddim7, Abdim7, and Bdim7 — all inversions of the same four notes.
How is Fdim7 used in music?
Fdim7 functions as the vii°7 chord in Gb Major, resolving up by half step. It also works as a chromatic passing chord and is common in classical music for dramatic tension and in jazz for smooth voice leading.
What songs use Diminished 7th chords?
Diminished 7th chords appear in Michelle (Beatles), throughout classical music by Chopin and Beethoven, and in jazz standards for chromatic passing movement. Film composers use dim7 for suspense and drama.
How many unique Diminished 7th chords exist?
Only three. Fdim7 shares its notes with Ddim7, Abdim7, and Bdim7. The other two unique groups are Cdim7 and C#dim7/Dbdim7. All 12 roots map to just three sounds.