A major thirteenth chord is created by adding a 13th degree to any major 11th chord. For example, a Cmaj13 chord contains the notes C, E, G, B, D, F and A (1, 3, 5, 7, 9, 11 and 13). The 11th degree is usually omitted because of its clash with the 13rd degree. Here are some common open Maj13th chord shapes.
Dmaj13
Ebmaj13
Emaj13
Fmaj13
F#maj13
Gmaj13
Cmaj13
Dbmaj13
Abmaj13
Amaj13
Bbmaj13
Bmaj13