Which notes are in the C7♯9 chord?

C7♯9 contains the notes C, E, G, A# and D#. Relative to the root these are the degrees 1 – 3 – 5 – ♭7 – ♯9.

How many ways can you play C7♯9?

Minory lists 2 guitar fingerings for C7♯9. They all produce the same chord — what changes is the voicing and where it sits on the neck.

Is the C7♯9 chord hard to play?

C7♯9 requires a barre, so it can feel demanding at first. Keeping the index finger straight and pressing from the wrist rather than the thumb makes it noticeably easier.

C dominant 7th sharp 9 · Guitar

C7♯9 Chord on Guitar

The C7♯9 chord (C dominant 7th sharp 9) is built from the notes C, E, G, A# and D#. 2 different guitar fingerings for it are shown below.

Chord diagrams

Position 1starts at fret 2

Fingering

string 6 (E): muted
string 5 (A): fret 3 — middle finger
string 4 (D): fret 2 — index finger
string 3 (G): fret 3 — ring finger
string 2 (B): fret 5 — little finger
string 1 (E): muted

Position 2starts at fret 9

Fingering

string 6 (E): muted
string 5 (A): muted
string 4 (D): fret 10 — middle finger
string 3 (G): fret 9 — index finger
string 2 (B): fret 11 — ring finger
string 1 (E): fret 11 — little finger

Notes in this chord

C
E
G
A♯
D♯

Degrees: 1 – 3 – 5 – ♭7 – ♯9

How to play

C7♯9 can be played with open strings on guitar, which makes it an accessible shape for beginners. Strings marked ○ ring open, while strings marked ✕ are muted.

Theory behind the chord

Often called the Hendrix chord, the 7♯9 stacks a sharpened ninth over a dominant seventh. Major and minor thirds sound at once, producing the gritty clash that defines psychedelic rock and funk. On C7♯9 this structure sits on the root C, so the degrees 1 – 3 – 5 – ♭7 – ♯9 map onto C, E, G, A# and D#.

Frequently asked questions

Which notes are in the C7♯9 chord?: C7♯9 contains the notes C, E, G, A# and D#. Relative to the root these are the degrees 1 – 3 – 5 – ♭7 – ♯9.
How many ways can you play C7♯9?: Minory lists 2 guitar fingerings for C7♯9. They all produce the same chord — what changes is the voicing and where it sits on the neck.
Is the C7♯9 chord hard to play?: C7♯9 requires a barre, so it can feel demanding at first. Keeping the index finger straight and pressing from the wrist rather than the thumb makes it noticeably easier.

Practise C7♯9 on your phone

Minory bundles the full chord library with a tuner, metronome and repertoire notebook — and it all works offline.