C#m9 piano chord — the keys, the inversions, the theory

C#m9 is a minor ninth chord built from C#, E, G#, B, D#. 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#m9

C# · E · G# · B · D#

Piano keyboardC4C5

Semitones above the root: 0 – 3 – 7 – 10 – 14

The third is minor — one semitone lower than in a major chord — which is where the darker colour comes from.

Inversions of C#m9

  • Root position

    C# · E · G# · B · D# · bass C#

  • Inversion 1

    E · G# · B · C# · D# · bass E

  • Inversion 2

    G# · B · C# · D# · E · bass G#

  • Inversion 3

    B · C# · D# · 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#m9

  • Evi
  • Bii

In E it does this job: I – V – vi – IV

  1. E
  2. B
  3. C#m9
  4. A

Questions