The co-crystal structure of 2,4-diamino-6-phenyl-1,3,5-triazine with 4-chlorobenzoic acid/4-methoxybenzoic acid molecules are explain the link between the dimension and shape of their hydrogen-bonded assembly. The co-crystal structure of 2,4-diamino-6-phenyl-1,3,5-triazine with 4-chlorobenzoic acid/4-methoxybenzoic acid forming a cyclic R-2(2)(8) ring motif via N-HMIDLINE HORIZONTAL ELLIPSISO and O-HMIDLINE HORIZONTAL ELLIPSISN hydrogen bonding interactions, to form a supramolecular heterosynthon. In both the co-crystal structures, self-association of 2,4-diamino-6-phenyl-1,3,5-triazine moieties are connected via N-H N-horizontal ellipsis . base pairs with cyclic R-2(2)(8) motif form a supramolecular homosynthon. In co-crystal II, the centrosymmetrically paired methoxy group of 4-methoxy benzoic acid form a supramolecular homosynthon via weak intermolecular C-H O-horizontal ellipsis . hydrogen bonds, generating R-2(2)(6) ring motif. Both the co-crystal structures are stabilized by weak aromatic pi-pi and C-Cl center dot center dot center dot pi stacking interactions. Hirshfeld surface and fingerprint plots were used to study the intermolecular interactions both of the crystal structures.