Cdim Guitar Chord
C Diminished · C–Eb–Gb
Cdim is the C diminished chord: C–Eb–Gb. Its sound is tense and unstable — stacked minor 3rds that work as dramatic passing chords.
You'll rarely sit on Cdim for a full bar — diminished chords are connectors. Classic uses: passing between the I and ii chords in B 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 Cdim is the neck voicing at the 1st fret (x 3 1 x 1 2, low E string to high E string). Below you'll find 7 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 Cdim: 7 Voicings
Frets are listed from the low E string to the high E string. x = don't play that string, 0 = open string.
Cdim Chord Theory
| Interval | R | ♭3 | ♭5 |
|---|---|---|---|
| Note | C | Eb | Gb |
Cdim is built from the C minor scale.
Cdim Chord FAQ
What notes are in the Cdim chord?
Cdim contains 3 notes: C (R), Eb (♭3), Gb (♭5). The interval formula for a diminished chord is R–♭3–♭5.
What is the easiest way to play Cdim on guitar?
Use the neck voicing at the 1st fret: x 3 1 x 1 2 (frets listed from the low E string to the high E string, x = don't play that string). Cdim has no open-position shape in standard tuning, so this movable form is the standard starting point.
Is Cdim a major or minor chord?
Cdim is built on a minor triad (C–Eb–Gb) with the ♭5 added, so it behaves as a minor-family chord.
What keys use the Cdim chord?
Cdim appears diatonically in Eb major (as vi), Bb major (as ii), and Ab major (as iii) — plus it's the home chord (i) of C minor.
Related Chords
Hear yourself play Cdim
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