1-(4-Chloro-2-fluoro-5-nitro-phen-yl)-4-difluoro-methyl-3-methyl-1H-1,2,4-triazol-5(4H)-one.

In the title compound, C(10)H(6)ClF(3)N(4)O(3), the dihedral angle between the benzene ring and the triazolone ring is 59.9†(1)°, while the nitro substituent subtends an angle of 39.5†(1)° to the benzene ring plane. In the crystal, pairs of mol-ecules form inversion dimers via C-H⋯O hydrogen bonds.