Chord
C♯ Add 9 Chord
Interactive keyboard
Highlighted notes form this chord.
Notes
C♯ · E♯ · G♯ · D♯
Root: C♯
Intervals
1 · 3 · 5 · 9
How it is built
This chord starts on C♯ and applies the intervals 1, 3, 5, 9. The result contains 4 distinct pitch classes per octave.
Explore related combinations
Guide and musical context
About C♯ Add 9 Chord
C♯ Add 9 Chord contains C♯, E♯, G♯, D♯. Its sound is clear and expansive, adding a ninth without a seventh.
Character and sound
Clear and expansive, adding a ninth without a seventh.
Musical context and history
Add9 chords became especially common in modern pop, rock and acoustic arranging because they enrich a triad while keeping a simple open structure.
How and where it is used
They work well as colored tonic or subdominant chords and in open-string voicings.
In Theory view you can hear the pitch collection without depending on a specific fingering. Then switch to Piano, Guitar, Ukulele or Mandolin to see how the same notes are physically distributed on each instrument.
Harmonic and musical relationships
From C♯, the dominant is A♭, the subdominant is F♯ and the relative minor is B♭. These relationships are useful starting points for progressions.
The formula on this page is 1 · 3 · 5 · 9 and, from C♯, produces the notes C♯ · E♯ · G♯ · D♯.
Frequently asked questions
What notes are in the C♯ Add 9 Chord?
The notes are C♯, E♯, G♯, D♯.
What is its interval formula?
The formula is 1 · 3 · 5 · 9.
How does it sound and what is it used for?
Clear and expansive, adding a ninth without a seventh. They work well as colored tonic or subdominant chords and in open-string voicings.
Can I view it on a specific instrument?
Yes. Use the selector near the top to switch between Piano, Guitar, Ukulele and Mandolin without changing the musical combination you are studying.