The maximum bite force for a human male with normal teeth is about 777 Newtons, or 174 pounds; for females, it is about 481 Newtons, or 101 pounds. For comparison, normal chewing exerts 70 pounds per square inch.
Human bite force differs throughout the jaw, as teeth closer to the hinge of the jaw are able to exert more pressure. Shorter jaws are consequently more efficient at generating powerful bites, but the heavier jaw musculature of the average man means they are able to bit harder than the average woman despite differences in jaw size. Older people and children both have less strong bite forces due to having less muscle to power the bite.