In the title β-thio-carbonyl compound, C16H16O2S, the carbonyl and meth-oxy O atoms are approximately coplanar [O-C-C-O torsion angle = -18.2 (5)°] and syn to each other, and the tolyl ring is orientated to lie over them. The dihedral angle between the planes of the two rings is 44.03 (16)°. In the crystal, supra-molecular chains are formed along the c axis mediated by C-H⋯O inter-actions involving methine and methyl H atoms as donors, with the carbonyl O atom accepting both bonds; these pack with no specific inter-molecular inter-actions between them.
In the title β-thio-carbonyl compound, C16H16O3S, the adjacent meth-oxy and carbonyl O atoms are synperiplanar [the O-C-C-O torsion angle is 19.8 (4)°] and are separated by 2.582 (3) Å. The dihedral angle between the rings is 40.11 (16)°, and the meth-oxy group is coplanar with the benzene ring to which it is connected [the C-C-O-C torsion angle is 179.1 (3)°]. The most notable feature of the crystal packing is the formation of methine and methyl C-H⋯O(carbon-yl) inter-actions that lead to a supra-molecular chain with a zigzag topology along the c axis. Chains pack with no specific inter-molecular inter-actions between them.