C#7 piano chord — the keys, the inversions, the theory

C#7 is a dominant seventh chord built from C#, E#, G#, B. Below: the keys to press, every inversion with its own diagram, the intervals it is made of, the keys whose scale contains it, and a progression that actually uses it. Press any diagram to hear it.

C#7

C# · E# · G# · B

Piano keyboardC4C5

Semitones above the root: 0 – 4 – 7 – 10

A major third with a flattened seventh above it: unstable on purpose, and it wants to resolve a fourth up.

Inversions of C#7

  • Root position

    C# · E# · G# · B · bass C#

  • Inversion 1

    E# · G# · B · C# · bass E#

  • Inversion 2

    G# · B · C# · E# · bass G#

  • Inversion 3

    B · C# · E# · G# · bass B

Same chord, different note at the bottom. Press a diagram to hear it — inversions are how you move between chords without jumping your hand across the keyboard.

Keys that contain C#7

  • F#V

In F# it does this job: I – V – vi – IV

  1. F#
  2. C#7
  3. D#m
  4. B

Questions