Read left to right, 6th string to 1st: a number is a fret, 0 is an open string, x is a string you do not play.
- Index finger on the 3rd fret of the A string (5th).
- Middle finger on the 4th fret of the D string (4th).
- Ring finger on the 4th fret of the B string (2nd).
- Little finger on the 5th fret of the G string (3rd).
- Do not play the low E string: start the strum from the A string.
- Stop the strum before the high E string, or let the underside of a fretting finger rest on it to keep it quiet.
String by string
What each string does in this shape, and which note of the chord it sounds. This is what to listen for when you pluck them one at a time.
| String | Fret | Finger | Note | In the chord |
|---|---|---|---|---|
| 6th (low E) | not played | — | — | — |
| 5th (A) | fret 3 | index | C3 | root |
| 4th (D) | fret 4 | middle | G♭3 | flat fifth |
| 3rd (G) | fret 5 | little | C4 | root |
| 2nd (B) | fret 4 | ring | E♭4 | minor third |
| 1st (high E) | not played | — | — | — |
One string at a time: a chord strummed into a microphone is several notes at once, and a single string is something the page can hear exactly. A string in tune but on the wrong fret, or deadened by the finger beside it, shows up here and not on a tuner. Tap a string to check it again.
Another way to play Cdim
The same 3 notes, somewhere else on the neck. A different shape puts a different note on top, so each one colours the chord slightly differently — and one of them is usually nearer the chord you are coming from.
- x-x-10-8-7-8A shape at the 7th fret · four fingers
Holding it cleanly
The lowest string is left out, because its open note is not in the chord. Aim the strum to start below it, or let the tip of a fretting finger rest against the unwanted string to keep it quiet.
The notes in Cdim
A diminished chord is built from the root (1), ♭3 and ♭5 of its root’s major scale. From C that gives C – E♭ – G♭. Two minor thirds stacked: tense and unstable, a passing chord between two steadier ones.
The same root, other chords: C major, Cm, C7, Cmaj7, Cm7, Csus2, Csus4, Caug.
Keys that use Cdim
Cdim is built from the notes of 2 keys. Each link is that key’s full set of guitar chords — the ones that sound right next to this one.
Frequently asked questions
What notes are in a Cdim chord?
C diminished is three notes: C – E♭ – G♭ — the root, ♭3 and ♭5 of the C major scale. On guitar the shape x3454x sounds C3, G♭3, C4 and E♭4, so some of those notes appear more than once.
What is the easiest way to play Cdim on guitar?
The usual shape is x3454x — a shape at the 3rd fret, with four fingers. It is already about as easy as this chord gets.
What is the difference between Cdim and Cm?
One note. Cdim is Cm with its fifth lowered a semitone, to G♭. That flattened fifth is a tritone above the root — the most unstable interval there is — which is why Cdim never sounds like a place to stop.
What keys is Cdim in?
Cdim is one of the seven chords of D♭ major (as vii°) and B♭ minor (as ii°).