Ope.math: Operator product expansions in free field realizations of conformal field theory. We present version 1.0 of the package “ope.math” for Mathematica to compute operator product expansions (OPEs) of composite operators (currents) in terms of free fields in conformal field theories. Further, we can also calculate OPEs of currents expressed by vertex operators. We give examples of free field realizations of current algebras, Hamiltonian reduction of current algebras and BRST cohomology of two-dimensional gravity coupled to $cleq 1$ minimal models.