Cdim7 chord on piano
Cdim7 is C, E♭, G♭ and B𝄫. C is the white key just left of the pair of black keys. Hit Play and watch each key light as it sounds.
root position · C–E♭–G♭–B𝄫 · right hand 1-2-3-5
- Notes
- C · E♭ · G♭ · B𝄫
- Formula
- 1 · ♭3 · ♭5 · ♭♭7
How to play Cdim7 on piano
Start on C, count 3 half steps up to E♭, 3 half steps up to G♭ then 3 half steps up to B𝄫. That's the whole chord: 4 keys.
- Right hand: 1 on C, 2 on E♭, 3 on G♭ and 5 on B𝄫.
- Left hand: 5 on C, 3 on E♭, 2 on G♭ and 1 on B𝄫.
- On the keyboard it's white, black, black and white keys, the same pattern as Gdim7, so your hand shape carries over.
Cdim7 inversions
- root position: C–E♭–G♭–B𝄫. RH 1-2-3-5.
- 1st inversion: E♭–G♭–B𝄫–C, E♭ lowest. Right hand 1-2-3-5.
- 2nd inversion: G♭–B𝄫–C–E♭ (G♭ in the bass). Right hand 1-2-3-5.
- 3rd inversion: B𝄫–C–E♭–G♭, with B𝄫 at the bottom. Fingers 1-2-3-5.
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 Cdim7 and its neighbours
These are the changes you'll meet most often with Cdim7, using the first shape of each chord.
- C♯ (leads up a half step): Cdim7 to C♯: play C♯ in root position (C♯–E♯–G♯), while C moves up to C♯, G♭ down to E♯ and B𝄫 down to G♯. C♯ on piano
- C♯m (leads up a half step): Cdim7 to C♯m: play C♯m in root position (C♯–E–G♯), while C moves up to C♯, E♭ up to E and B𝄫 down to G♯. C♯m on piano
- F (a fifth down): Cdim7 to F: play F in 2nd inversion (C–F–A) and C and A stay under the same fingers, while G♭ moves down to F. F on piano
Cdim7 is a diminished seventh: three minor thirds stacked, so the chord divides the octave into four equal parts. Cdim7 can stand in for a dominant seventh a half step below, which is why it links chords so smoothly. The one-by-one button above makes that quality easy to hear.
Practice Cdim7 in two minutes
Roll the chord up and back down, C, E♭, G♭, B𝄫, G♭, E♭, C, before playing it as a block. Finish with the inversions in order: C–E♭–G♭–B𝄫; E♭–G♭–B𝄫–C; G♭–B𝄫–C–E♭; B𝄫–C–E♭–G♭.
The keys of Cdim7
Cdim7 is a diminished seventh chord, 1–♭3–♭5–♭♭7 from C. Root position, from the bottom: how Cdim7 is built.
| Note | Key | Fingers | Role |
|---|---|---|---|
| C | white key | RH 1 · LH 5 | root |
| E♭ | black key | RH 2 · LH 3 | minor third |
| G♭ | black key | RH 3 · LH 2 | diminished fifth |
| B𝄫 | white key | RH 5 · LH 1 | diminished seventh |
Cdim7 in context
Cdim7 on guitar and ukulele
Cdim7 on guitar and ukulele uses the same 4 notes in a different layout. See all three together.
Related C chords on piano
Other diminished seventh chords
Cdim7 on piano: questions
What notes are in Cdim7 on piano?
C, E♭, G♭ and B𝄫: C (white key), E♭ (black key), G♭ (black key) and B𝄫 (white key). Right hand 1-2-3-5, left hand 5-3-2-1.
How do you play Cdim7 on piano?
Press C, E♭, G♭ and B𝄫 together (2 black, 2 white). Right hand: 1 on C, 2 on E♭, 3 on G♭ and 5 on B𝄫.
What are the inversions of Cdim7?
1st inversion (E♭–G♭–B𝄫–C), 2nd inversion (G♭–B𝄫–C–E♭) and 3rd inversion (B𝄫–C–E♭–G♭), after root position (C–E♭–G♭–B𝄫). Each keeps all the notes of the chord.
What does Cdim7 look like on the keyboard?
white, black, black and white keys, the same pattern as Gdim7, so one hand shape covers all of them.
Checked automatically: no shape here plays a note outside Cdim7. Updated September 2026.