C diminished chord on piano (Cdim)
Cdim is C, E♭ and G♭. C is the white key just left of the pair of black keys. Press Play to hear it, then try it at half speed.
root position · C–E♭–G♭ · right hand 1-3-5
- Notes
- C · E♭ · G♭
- Formula
- 1 · ♭3 · ♭5
How to play Cdim on piano
Start on C, count 3 half steps up to E♭ then 3 half steps up to G♭. Press the 3 keys together and that's Cdim.
- Right hand: 1 on C, 3 on E♭ and 5 on G♭.
- Left hand: 5 on C, 3 on E♭ and 1 on G♭.
- On the keyboard it's white, black and black keys, the same pattern as Gdim, so your hand shape carries over.
Cdim inversions
- root position: C–E♭–G♭. RH 1-3-5.
- 1st inversion: E♭–G♭–C, E♭ lowest. Fingers 1-2-5.
- 2nd inversion: G♭–C–E♭, G♭ lowest. Right hand 1-3-5.
Use the inversions to stay put: the next chord is often one inversion away from where your hand already is, as the changes below show.
Moving between Cdim and its neighbours
These are the changes you'll meet most often with Cdim, using the first shape of each chord.
- C♯ (leads up a half step): Cdim to C♯: play C♯ in root position (C♯–E♯–G♯), while C moves up to C♯, E♭ up to E♯ and G♭ up to G♯. C♯ on piano
- C♯m (leads up a half step): Cdim to C♯m: play C♯m in root position (C♯–E–G♯), while C moves up to C♯, E♭ up to E and G♭ up to G♯. C♯m on piano
- Fm (iii in D♭ major): Cdim to Fm: play Fm in 2nd inversion (C–F–A♭) and C stays under the same finger, while E♭ moves up to F and G♭ up to A♭. Fm on piano
Cdim is a diminished triad: two minor thirds stacked. Cdim rarely stays long; it's a passing chord that usually climbs a half step to the next chord. Play it solid and then broken to hear the difference.
Practice Cdim in two minutes
Start with a broken chord, C E♭ G♭ E♭ C, then play it solid. Next, walk up through C–E♭–G♭ → E♭–G♭–C → G♭–C–E♭ without lifting your eyes to your hand.
The keys of Cdim
Cdim is a diminished chord, 1–♭3–♭5 from C. Root position, from the bottom: how Cdim is built.
| Note | Key | Fingers | Role |
|---|---|---|---|
| C | white key | RH 1 · LH 5 | root |
| E♭ | black key | RH 3 · LH 3 | minor third |
| G♭ | black key | RH 5 · LH 1 | diminished fifth |
Cdim in context
Cdim on guitar and ukulele
The same notes on another instrument: Cdim on guitar and Cdim on ukulele. This page puts all three side by side.
Close to Cdim
Other diminished chords
Cdim on piano: questions
What notes are in Cdim on piano?
C, E♭ and G♭: C (white key), E♭ (black key) and G♭ (black key). Right hand 1-3-5, left hand 5-3-1.
How do you play Cdim on piano?
Press C, E♭ and G♭ together (2 black, 1 white). Right hand: 1 on C, 3 on E♭ and 5 on G♭.
What are the inversions of Cdim?
1st inversion (E♭–G♭–C) and 2nd inversion (G♭–C–E♭), after root position (C–E♭–G♭). Only the lowest note changes.
What does Cdim look like on the keyboard?
white, black and black keys, the same pattern as Gdim, so one hand shape covers all of them.
Checked automatically: no shape here plays a note outside Cdim. Updated September 2026.