In the title compound, C 9H 8O 2, an intra-molecular O - H?O hydrogen bond generates an S(6) ring. The dihedral angle between the mean plane of the S(6) ring and the benzene ring is 1.89 (2)°. In the crystal, inversion-related molecules are linked by pairs of O - H?O hydrogen bonds, forming a cyclic dimers with R 2 2(12) graph-set motif. Weak intermolecular C - H?Ocarbon-yl and C - H?Ohydroxy hydrogen bonds link the dimers into chains along [010], generating two C(6) motifs that overlap three C atoms, forming R 2 2(8) ring motifs.
