The A-flat major eleventh chord (abbreviated "Abmaj11 chord") is a six-note chord consisting of the notes A, C, E, G, B, and D. The chord is formed by adding an eleventh to a A-flat major ninth chord.

In practice, the fifth (E) is often omitted from the Abmaj11 chord to avoid a very dissonant sound, and because it's not always possible to play all notes simultaneously.

Name
A-flat major eleventh chord
Notes
A C E G B D
Intervals
1 3 5 7 9 11
Chord symbol
Amaj11
Alternative symbols
A11 Ama11 AMA11 AM11
Type
hexad (six-note chord)

Abmaj11 chord on piano

Abmaj11 chord on guitar

Abmaj11 chord on ukulele

Abmaj11 chord on the staff