Cdim
C Diminished — tense and unstable by design — built from stacked minor thirds, it begs to resolve.
The keys
C – E♭ – G♭
What's inside Cdim
| Note | Interval from root | Degree |
|---|---|---|
| C | Root | 1 |
| E♭ | Minor 3rd | b3 |
| G♭ | Diminished 5th | b5 |
Inversions
| Position | Keys (low → high) |
|---|---|
| Root position | C4 – E♭4 – G♭4 |
| 1st inversion | E♭4 – G♭4 – C5 |
| 2nd inversion | G♭4 – C5 – E♭5 |
A working voicing
Split the chord between two hands the way working players do — a solid shell low down, the colour tones up top:
| Hand | Keys |
|---|---|
| Left (shell) | C2 – C3 |
| Right (colour) | E♭4 – G♭4 |
Where Cdim lives
As the I chord
Cdim → F → G → Cdim
The classic I–IV–V–I motion with this chord as home.
In a ii–V–I
Dm7 → G7 → Cdim
The strongest cadence in harmony, resolving onto this chord.
Put Cdim under your fingers
Hear every voicing, see the keys light up, and drill it in the interactive Chord & Voicing Lab.
Open the Chord & Voicing Lab →