A variable face thickness pattern is determined for a golf club head by setting a target value for a first constraint. Parametrization zones are defined and values set for a first parameter and a second parameter for each parametrization zone. Resultant first constraint values are evaluated from simulated impacts against the target first constraint value and the values are changed for the first and second parameters to result in a simulated face thickness pattern. In one aspect, the club head has a maximum coefficient of restitution at a first location of the striking face and a second coefficient of restitution that is no less than 98% of the maximum coefficient of restitution at a second location that is at least 7.5 mm from the first location. In another aspect, the club head has a moment of inertia, Izz, and a mass, mh, satisfying: Izz>mh*9.3 cm2.