The C-flat major thirteenth chord (abbreviated "Cbmaj13 chord") is a seven-note chord consisting of the notes C, E, G, B, D, F, and A. The chord is formed by adding a thirteenth to a C-flat major eleventh chord.

In practice, the fifth (G) and eleventh (F) are often omitted from the Cbmaj13 chord to avoid a very dissonant sound, and because it's not always possible to play all notes simultaneously.

Name
C-flat major thirteenth chord
Notes
C E G B D F A
Intervals
1 3 5 7 9 11 13
Chord symbol
Cmaj13
Alternative symbols
C13 Cma13 CMA13 CM13
Type
Heptad (seven-note chord)

Cbmaj13 chord on piano

Cbmaj13 chord on guitar

Cbmaj13 chord on ukulele

Cbmaj13 chord on the staff