C# Add 9
Notes:C# – F – G# – D#
Formula:R-M3-P5-M9
Intervals:P1-M3-P5-M9
Scale Degrees:1-3-5-9
Introduction
The C# Add 9 piano chord (C#add9) consists of the notes C#, F, G#, D#. It is a major triad with an added major 9th without the 7th, giving it a bright, open character that adds color to a major chord without the 7th. Formula: R-M3-P5-M9 | Scale degrees: 1-3-5-9.
Enharmonic equivalent: C♯ is enharmonically equivalent to D♭. See Db Add 9.
Notes
C# Add 9 Inversions
| Position | Notes |
|---|---|
| Root Position | C#4 – F4 – G#4 – D#5 |
| 1st Inversion | F4 – G#4 – C#5 – D#5 |
| 2nd Inversion | G#4 – C#5 – D#5 – F5 |
| 3rd Inversion | C#4 – F4 – G#4 – D#4 |
Key Signature
The key of C# Add 9 has 7 sharps: F♯, C♯, G♯, D♯, A♯, E♯, B♯.
F♯C♯G♯D♯A♯E♯B♯
Theory: Intervals
Formula: R-M3-P5-M9
Intervals: P1-M3-P5-M9
The C# Add 9 is built by stacking intervals from the root note. The formula R-M3-P5-M9 describes the scale degrees used. The intervals P1-M3-P5-M9 show the distance between each note in the chord.
C# Add 9 — Frequently Asked Questions
What notes are in the C# Add 9 chord?
C# Add 9 is built from the C# root. Check the interactive keyboard above for exact notes and fingering.
How is the C# Add 9 chord used in music?
C# Add 9 appears in jazz, pop, and classical contexts. Its sound depends on the chord quality (Add 9).
What is the fingering for C# Add 9?
See the fingering chart above. Right hand typically uses thumb on root. Left hand uses pinky on root.
What are the inversions of C# Add 9?
Use the inversion buttons above to see each inversion with notes, fingering, and staff notation.
Practice Tips
- Major triad plus the 9th — no 7th.
- Open, modern pop sound.
- Simpler than a full 9th chord.
- Compare with C#9.
- Common in pop and worship music.
- Bright, spacious quality.