Embodiments of golf club heads comprising a face with a variable thickness to improve the durability in the club head, increase ball speed, and increase characteristic time (CT) are described herein. The face comprises thickened and thinned regions. The face includes a perimeter thickened region positioned near a perimeter of the face, a thinned region positioned inward of the perimeter thickened region toward a center of the face, and a central thickened region positioned over the center of the face. The combination of the thickened and thinned regions of the face increase ball speed and further increase or maximize CT without sacrificing durability.