The F Dominant 9th chord is a five-note chord made up of F, A, C, E♭, and G. It is built from a root, major third, perfect fifth, minor seventh, and major ninth.
Construction
F Dominant 9th = Root + Major 3rd + Perfect 5th + Minor 7th + Major 2nd = F · A · C · E♭ · G
| Note | Interval | Degree |
|---|---|---|
| F | Root | 1 |
| A | Major 3rd | 3 |
| C | Perfect 5th | 5 |
| E♭ | Minor 7th | ♭7 |
| G | Major 2nd | 9 |
Key Signature
A dominant chord points home to the key a fifth below its root: the F Dominant 9th is the V (dominant) of A# Major, so the relevant key signature is that key’s — 2 flats (B♭, E♭). Spelled as a scale, these notes are F Mixolydian.
B♭E♭
Order of flats
Flats are added in a fixed order — the reverse of the sharp order. Each new flat key adds the next flat on the list.
B♭E♭A♭D♭G♭C♭F♭
Mnemonic: Battle Ends And Down Goes Charles’ Father
Chords in the Key of A♯ Major
These are the triads built on each degree of the A♯ major scale:
F Dominant 9th — Frequently Asked Questions
What is the F Dominant 9th chord on piano?
The F Dominant 9th chord contains the notes F – A – C – E♭ – G. On piano, play these notes together to sound the chord.
What notes are in the F Dominant 9th chord?
The F Dominant 9th chord (F9) contains 5 notes: F, A, C, Eb, G. Formula: R-M3-P5-m7-M9.
How is F9 used in music?
F9 is used in jazz, fusion, and contemporary music to add harmonic color. It appears as a dominant or tonic chord depending on context.
What is the scale degree formula for F9?
F9 uses scale degrees 1-3-5-b7-9, giving it its distinctive sound.