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C9 Chord

C9 is a dominant seventh plus D, the ninth. Its full spelling has five different notes, so a practical guitar or ukulele grip may leave out a less essential chord tone.

  • Notes: C-E-G-B flat-D
  • Symbol: C9
  • V9 in F major
  • Seventh and ninth
Switch chordC9

How to play a C9 chord

Notes: C - E - G - Bb - D · symbol C9

  • Root position

    C - E - G - Bb - D
    C4C5

  • 1st inversion

    E - G - Bb - D - C
    C4C5

  • 2nd inversion

    G - Bb - D - C - E
    C4C5

  • 3rd inversion

    Bb - D - C - E - G
    C4C5

Where does C9 belong?

In F major, C9 extends the V7 chord before it resolves to the tonic.
Play the role cards to hear how its surrounding chords change the job it does; Diatonic Chords explains the basic numbered roles.

  • In F majorDominant with a ninth
    V9

    A V7 with the ninth on top: the same pull to F, a fuller sound.

    FIBbIVC9V9FI
  • In C bluesFunk and blues home
    I9

    In funk and blues this is a home chord that never has to resolve.

    C9I9F9IV9C9I9G9V9

Progressions to try

  • FBbC9F

    C9 is V9 in F major; its seventh keeps the dominant pull while the ninth adds another voice.

  • C9F9C9G9

    Treat the repeated C9 as a blues home chord, then hear the other ninth chords answer it.

Which shape should you use?

On guitar, the open shape x30310 is the easiest place to start. The barre shape 8-10-8-9-8-10, at the 8th fret, moves the chord up the neck and sits well between other barre chords.

On ukulele, the open shape 3203 is the easiest place to start. 5465 gives a higher version.

On piano, spread the five-note spelling across both hands: C-E-G-B flat-D. Move C up an octave to reach the first inversion, E-G-B flat-D-C; the notes remain the same while the lowest voice changes.

What are the inversions?

The first four notes, C-E-G-B flat, form the dominant seventh. D adds the ninth.

  • Root position: C-E-G-B flat-D, with C lowest.
  • First inversion: E-G-B flat-D-C, written C9/E if E is lowest in the whole arrangement.
  • Second inversion: G-B flat-D-C-E, written C9/G if G is lowest in the whole arrangement.
  • Third inversion: B flat-D-C-E-G, written C9/Bb if B flat is lowest in the whole arrangement.
  • Fourth inversion: D-C-E-G-B flat, written C9/D if D is lowest in the whole arrangement.

A slash chord names the note in the bass, not merely the lowest note under one hand. Chord Inversions shows how to read that distinction.

How does C9 differ from C7?

Remove the ninth, D, and the remaining notes form C7. The seventh stays, so both chords can still pull toward the same tonic. Try that one-note change on piano, then use the comparer to hear it in the full chord. See C7 for the other chord's full spelling and roles.

  • C9

    C - E - G - Bb - D
    C4C5

    C dominant 9

  • C7

    C - E - G - Bb
    C4C5

    C dominant 7

Try another chord