Which notes are in the C#dim7 chord?

C#dim7 contains the notes C#, E, G and A#. Relative to the root these are the degrees 1 – ♭3 – ♭5 – ♭♭7.

Are C#dim7 and Dbdim7 the same chord?

Yes. C#dim7 and Dbdim7 are enharmonically identical — the spelling differs but the frets and keys are the same. Which name is used depends on the key of the piece.

C# diminished 7th · Piano

C#dim7 Chord on Piano

The C#dim7 chord (C# diminished 7th) is built from the notes C#, E, G and A#. The keyboard diagram below shows exactly which keys to press. The same chord is also written Dbdim7; both spellings sound identical.

Chord diagrams

C#dim7

Notes in this chord

C♯
E
G
A♯

Degrees: 1 – ♭3 – ♭5 – ♭♭7

Also written: Dbdim7

How to play

To play C#dim7 on piano, press C#, E, G and A# together. In root position the lowest note is C#, and the finger numbers follow the keys left to right in the diagram.

Theory behind the chord

Diminished seventh chords divide the octave into four equal minor thirds. Every inversion sounds the same, so a single shape can be slid up the neck to lead into several different keys. On C#dim7 this structure sits on the root C#, so the degrees 1 – ♭3 – ♭5 – ♭♭7 map onto C#, E, G and A#.

Frequently asked questions

Which notes are in the C#dim7 chord?: C#dim7 contains the notes C#, E, G and A#. Relative to the root these are the degrees 1 – ♭3 – ♭5 – ♭♭7.
Are C#dim7 and Dbdim7 the same chord?: Yes. C#dim7 and Dbdim7 are enharmonically identical — the spelling differs but the frets and keys are the same. Which name is used depends on the key of the piece.

Practise C#dim7 on your phone

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