Fdim Guitar Chord
F Diminished · F–Ab–Cb
Fdim is the F diminished chord: F–Ab–Cb. Its sound is tense and unstable — stacked minor 3rds that work as dramatic passing chords.
You'll rarely sit on Fdim for a full bar — diminished chords are connectors. Classic uses: passing between the I and ii chords in E major, or substituting for the V7♭9 a half-step below. The symmetrical shape repeats every three frets, so one grip gives you four chords.
The most common way to play Fdim is the diminished grip at the 1st fret (1 x 3 4 x 4, low E string to high E string). Below you'll find 3 ways to play it across the neck, from open position to barre and shell voicings, with the theory behind the chord and the progressions it lives in.
How to Play Fdim: 3 Voicings
Frets are listed from the low E string to the high E string. x = don't play that string, 0 = open string.
Fdim Chord Theory
| Interval | R | ♭3 | ♭5 |
|---|---|---|---|
| Note | F | Ab | Cb |
Fdim is built from the F minor scale.
Fdim Chord FAQ
What notes are in the Fdim chord?
Fdim contains 3 notes: F (R), Ab (♭3), Cb (♭5). The interval formula for a diminished chord is R–♭3–♭5.
What is the easiest way to play Fdim on guitar?
Use the diminished grip at the 1st fret: 1 x 3 4 x 4 (frets listed from the low E string to the high E string, x = don't play that string). Fdim has no open-position shape in standard tuning, so this movable form is the standard starting point.
Is Fdim a major or minor chord?
Fdim is built on a minor triad (F–Ab–Cb) with the ♭5 added, so it behaves as a minor-family chord.
What keys use the Fdim chord?
Fdim appears diatonically in Ab major (as vi), Eb major (as ii), and Db major (as iii) — plus it's the home chord (i) of F minor.
Related Chords
Hear yourself play Fdim
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