C♯dim

C♯1E♭3G♭5

Two minor thirds stacked. The fifth is diminished, so it cannot be dropped without losing the chord.

Written the other way round it is D♭dim — the same twelve keys on a piano, a different piece of notation.

on guitar on piano the scale

Every fingering that fits a hand

Fig. 2

6704

easy

Fig. 3

6434

hard

Fig. 4

643x

easy

Fig. 5

6797

hard

What is true of it

C♯dim is C♯, E and G — 1, b3 and b5 counted from C♯.

The easiest of the 4 fingerings below is 6704: 3 fingers, held at the 4th fret.

None of them uses an open string, so this chord moves up the neck unchanged — the same shape 1 fret higher is the chord a semitone above.

Where its notes are on the neck

Fig. 6 — first 12 frets

The brass dots are C♯, the root. Everything else is a chord tone with its degree printed in it.

With a different note underneath

first inversion

C♯dim/E

x434

second inversion

C♯dim/G

010x

An inversion is the same chord with a different note lowest. The name changes to a slash name because the bass is what a listener hears as the foundation.

C♯ in other shapes

C♯major C♯mminor C♯augaugmented C♯5power chord C♯sus2suspended second C♯sus4suspended fourth

Cdim Ddim D♯dim E♭dim Edim Fdim F♯dim G♭dim all 374