The short version
- Cadd9 is C add nine. Its notes are C, E, G and D (formula 1 – 3 – 5 – 9).
- Easiest way to play it: the open shape, frets x 3 2 0 3 0 from low E to high E (x = don’t play).
- It sounds bright, pretty and modern. Drop it in wherever you’d play the plain major chord. It works especially well on the I and IV chords.
- Cadd9 turns up in 6 keys: C major (as the Iadd9), G major (as the IVadd9), F major (as the Vadd9), A minor (as the IIIadd9) and E minor (as the VIadd9), and more in the table below.
- Try it in: Cadd9 – G – Am – Fadd9, the four-chord song, with fairy lights.
How to play Cadd9 on guitar, step by step
Start with the shape marked “Start here” above: the open chord, the easiest way in.
- Put your index finger on fret 2 of the 4th (D) string.
- Put your middle finger on fret 3 of the 5th (A) string.
- Put your ring finger on fret 3 of the 2nd (B) string.
- Let the G and high E strings ring open.
- Don’t play the low E string: skip it, or touch it lightly with a spare finger so it can’t ring.
- Strum from the 5th (A) string down, then press Strum on this page to check it sounds the same.
Once that’s comfy, try the other 2 shapes. Shape 2 is the barre chord, root on the 5th string (3rd fret): x 3 5 7 5 3. Shape 3 is the barre chord, root on the 6th string (8th fret): 8 10 12 9 8 8. Same chord, different spot on the neck, which helps when the next chord lives nearby.
Buzzing? Press just behind the fret wire, not in the middle of the fret, and come down on your fingertips so they don’t touch the next string. Then press Strum and play along: if yours sounds duller, one string is muted somewhere.
Notes in the Cadd9 chord
Cadd9 is built from 4 notes. On guitar you’ll often play some of them twice, on different strings. That’s normal; the chord is still Cadd9.
| Note | Interval | What it does |
|---|---|---|
| C | 1 root | Names the chord and anchors the bass. |
| E | 3 major third | Makes it major (happy). |
| G | 5 perfect fifth | Adds weight; often the first note left out. |
| D | 9 ninth | Sparkle on top. |
What Cadd9 sounds like, and when to use it
A major chord with the ninth sprinkled on top, and no seventh. It does the same job as the major chord, only prettier. Acoustic pop’s favourite seasoning. Drop it in wherever you’d play the plain major chord. It works especially well on the I and IV chords.
What key is Cadd9 in?
Cadd9 turns up in 6 keys: C major (as the Iadd9), G major (as the IVadd9), F major (as the Vadd9), A minor (as the IIIadd9) and E minor (as the VIadd9), and more in the table below. Tap a key to see the rest of its chords on the circle of fifths.
| Key | Numeral | Spelled as |
|---|---|---|
| C major | Iadd9 | Cadd9 |
| G major | IVadd9 | Cadd9 |
| F major | Vadd9 | Cadd9 |
| A minor | IIIadd9 | Cadd9 |
| E minor | VIadd9 | Cadd9 |
| D minor | VIIadd9 | Cadd9 |
Chords that go with Cadd9
Here’s a progression to try: Cadd9 – G – Am – Fadd9 (Iadd9–V–vi–IVadd9), the four-chord song, with fairy lights.
More progressions → Transpose it →
Using Cadd9 in a Suno prompt
Suno pays attention to chord names in a style prompt, at least some of the time. Put the progression in, keep the BPM, and let it fill in the rest. Then compare its guitar part with the shapes above.
Acoustic pop, 92 BPM, chord progression Cadd9 – G – Am – Fadd9, sparkly add9 acoustic guitar chords, gentle piano, soft strings, warm duet vocals, romantic
Cadd9 chord FAQ
What notes are in the Cadd9 chord?
Cadd9 has 4 notes: C (the root), E (the major third), G (the perfect fifth) and D (the ninth). The chord formula is 1 – 3 – 5 – 9.
How do you play Cadd9 on guitar?
The easy way is open chord. Strings from low E to high E: x 3 2 0 3 0 (x means don’t play that string). Put your index finger on fret 2 of the 4th (D) string. Put your middle finger on fret 3 of the 5th (A) string. Put your ring finger on fret 3 of the 2nd (B) string. Let the G and high E strings ring open. Don’t play the low E string: skip it, or touch it lightly with a spare finger so it can’t ring.
What does the “add9” in Cadd9 mean?
It tells you the chord type: Cadd9 is C add nine. A major chord with the ninth sprinkled on top, and no seventh. It does the same job as the major chord, only prettier. Acoustic pop’s favourite seasoning.
What key is Cadd9 in?
Cadd9 turns up in 6 keys: C major (as the Iadd9), G major (as the IVadd9), F major (as the Vadd9), A minor (as the IIIadd9) and E minor (as the VIadd9), and more in the table below. Major keys: C major, G major, F major. Minor keys: A minor, E minor, D minor.
What is the difference between Cadd9 and C9?
Cadd9 is a major chord plus the ninth (D) with no seventh, so it stays sweet. C9 also has the flat seventh (B♭), which makes it bluesy and funky.
What chords go well with Cadd9?
Try C, Fadd9, G and Am. The progression Cadd9 – G – Am – Fadd9 (Iadd9–V–vi–IVadd9) is the four-chord song, with fairy lights. Press Play progression on this page to hear it.
Other add9 chords
Got the chord? Now write the song
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