F add9
The F add9 chord consists of the F (Perfect unison), A (Major third), C (Perfect fifth) and G (Major ninth) notes.

How to play the F add9 chord
- Find F (Root) on the piano keyboard
- Add A (Major third) — 4 semitones above F
- Add C (Perfect fifth) — 7 semitones above F
- Add G (Major ninth) — 14 semitones above F
- Press all 4 notes simultaneously to sound the F add9 chord