C sharp diminished seventh piano chord - C#dim7

The C sharp diminished seventh chord is a 4-note chord consisting of the notes C#, E, G and Bb.
You can see these notes highlighted in the interactive piano chart below.
The chord itself is often abbreviated as C#dim7.

Interactive piano diagram for the C sharp diminished seventh chord

Piano keyboard displaying the C sharp diminished seventh chord with the notes Fb E G C# Db A# Bb

Reduced chords

Chords that are a subset of C#dim7. These contain less notes but all of them are included in C#dim7.

C sharp diminished seventh piano chord chart image

In case you prefer a non-interactive variant of the chord chart, we've embedded a PNG image below that shows the notes for the the C#dim7 chord. Feel free to save or share the image as needed.

Piano chord chart for the C sharp diminished seventh chord (C#dim7). The notes C#, E, G and Bb are highlighted.