A thirteenth chord is created by adding a 13th degree to any dominant 11th chord. For example, a C13 chord contains the notes C, E, G, Bb, D, F and A (1, 3, 5, b7, 9, 11 and 13). The 11th degree is usually omitted because of its clash with the 13rd degree.
F13

F#13

G13

Ab13

A13

C13

Db13

D13

Eb13

E13

Bb13

B13
