F Diminished Chord (Fdim)

1Composition: what it contains

F – A♭ – C♭

Symbol

Fdim

Also written

Fdim, F°, Fm♭5, Fmi(♭5)

Formula

1 ♭3 ♭5

2Appearance: diagrams and sound

On the guitar

On the ukulele

On the piano

On the staff

On bass and as an arpeggio

3Indications: what it is used for

The vii° chord of a major key and the ii° chord of a minor key are diminished triads. It works as a leading-tone chord resolving to the tonic (vii°–I), as a passing chord between two diatonic chords (for example between I and ii, or IV and V), and as an incomplete dominant seventh: the vii° triad contains the 3, 5 and 7 of V7. Classical, jazz, gospel and film music use it for tension and chromatic movement in the bass.

4Dosage: how to practise it

On piano, play the triad in all inversions at 60 BPM, then practise vii°6–I resolutions with smooth voice leading (the diminished fifth contracting to a third). On guitar, learn the compact three-string shapes on the top strings and the shape rooted on the fifth string. Practise the passing progression I–♯I°–ii–V slowly, then at 80–100 BPM. Arpeggiate 1-♭3-♭5 on bass. Five minutes a day is enough once the shapes are known.

5Warnings and common mistakes

Do not confuse the triad (dim) with the diminished seventh chord (dim7 or °7) or the half-diminished seventh (m7♭5 or ø7): many charts write 'dim' when they mean the four-note dim7, so check the style. The diminished fifth is not a perfect fifth; on guitar, power-chord habits make players play the wrong fifth. In root position the triad can sound harsh; first inversion is the most common classical voicing.

6Interactions with chords, scales and keys

Inversions

• Inversion 1 · Fdim/A♭ · A♭ – C♭ – F Play
• Inversion 2 · Fdim/C♭ · C♭ – F – A♭ Play

Scales to play over Fdim

• F Locrian Mode
• F Blues Scale
• F Half-Whole Diminished Scale
• F Whole-Half Diminished Scale
• F Hungarian Minor Scale
• E sharp Altered Scale

Where it appears (keys and Roman numerals)

• vii° – Key of F sharp Major
• vii° – Key of G flat Major
• ii° – Key of D sharp Minor
• ii° – Key of E flat Minor

7Other presentations available

The same chord from every note

Cdim C♯dim Ddim E♭dim Edim F♯dim Gdim A♭dim Adim B♭dim Bdim

Other chords on F

F Fm Faug Fsus2 Fsus4 F5 F6 Fm6 F7 Fmaj7 Fm7 Fm7♭5 Fdim7 Fm(maj7) F7sus4 Fadd9 Fm(add9) F6/9 F9 Fmaj9 Fm9 F11 Fm11 F13 F7♭9 F7♯9 F7♯5 F7♭5