A gasket cutting assembly for cutting an inner diameter and an outer diameter of a gasket simultaneously. The assembly has a rectangular bar base portion with a longitudinal slot therein and a blade at one end. An L-shaped adapter arm with a second blade at the L-shaped end also has a longitudinal slot and the arm and base are attached to one another by a bolt through the longitudinal slots. Graduations on the base and arm facilitate settings of the blades for cutting the internal and outside diameters of a gasket simultaneously.
