C diminished
How to play Cdim — Diminished
Cdim (Diminished)C · E♭ · G♭
Piano samples: Salamander Grand Piano (CC-BY 3.0)
C diminished — notes and structure
The Cdim chord stacks minor thirds up to the flattened fifth — tense and unstable, wanting to resolve.
The Cdim diminished consists of the notes C, E♭, G♭. Its interval structure is R–3–5 — the root, then each chord tone stacked above it. This is the same chord you see in the interactive finder above, drawn on the piano keyboard with the root circled and every chord tone labelled.
Cdim stacks a minor third (E♭) and a diminished fifth (G♭) above the root C.
To play Cdim, press the keys C, E♭, G♭ together — the root C is circled on the interactive keyboard above.
What key is Cdim in?
Every note of Cdim belongs to the scales below, so the chord sounds at home in each of these keys — the roman numeral is the degree it sits on.
- D♭ major — the vii° chord
- B♭ minor — the ii° chord
Chords that go with Cdim
In D♭ major, the chords built on the first, fourth and fifth degrees carry most songs — put Cdim next to these:
Frequently asked questions
- What notes are in the C diminished chord on piano?
- The Cdim chord is made of the notes C, E♭, G♭. It stacks minor thirds up to the flattened fifth — tense and unstable, wanting to resolve.
- How do you play C diminished on the piano?
- Press C, E♭, G♭ at the same time, with the root C as the lowest note. The interactive keyboard above lights up the exact keys.
- What is the diminished chord formula?
- Its interval structure is R–3–5 above the root — the same shape transposed to any of the twelve keys.
- What key does Cdim belong to?
- Cdim fits D♭ major (where it is the vii° chord), B♭ minor (where it is the ii° chord) — every note of the chord is in those scales.