A♭add9 — A♭, C, E♭, B♭ — is an add9 chord: major triad + 9th (no 7th in between) — a brighter alternative to a plain major chord, popular in pop, indie, and modern songwriting.
Intervals
The Ab add 9 chord stacks two thirds on the root. Each interval and its size in semitones:
- Ab→Cmajor 3rd4 semitones
- C→Ebminor 3rd3 semitones
- Eb→Bbperfect 5th7 semitones
On the keyboard
Each note of the Ab add 9 chord highlighted on a piano. Pitch class is what matters — any octave works.
On the guitar
One voicing of the Ab add 9 chord on a six-string guitar fretboard.
- 1Ab
- 3C
- 5Eb
- 9Bb
Common mistakes
The defining note is the 9th (B♭). It sits more than an octave above the root, which is why the chord needs a wide voicing — in tight piano voicings the 9th usually appears in the top register while the root and lower triad tones cluster below.
In context
Functions as a bright tonic alternative in major-key pop, country, and modern songwriting.
Drill it
The Ab add 9 chord is one of 48 in the Chord Trainer. Open the full trainer to practice it alongside related chords with timing and best-time tracking.
Open the Chord Trainer →Or try today's Etudle puzzleRelated
Frequently asked
- What notes are in a A♭add9 chord?
- A♭add9 contains four notes: A♭, C, E♭, B♭.
- How is A♭add9 different from A♭maj7?
- A♭add9 adds the 9th (B♭) on top of the underlying 7th chord. The 9th extends the chord into the next octave and adds harmonic colour.
- When is A♭add9 used in music?
- Functions as a bright tonic alternative in major-key pop, country, and modern songwriting.