According to a 1994 study by Zhao Y and Ye D, published in Pub Med, human males can generate approximately 120 kilograms of force. This is equal to about 265 pounds of force. Females generate slightly less powerful, but comparable, forces.
Humans generate the highest amount of force to their first molars. Humans only impart about 43 kilograms of force with their incisors, and about 99 kilograms of force with their bicuspids. Surprisingly, humans bite much harder than any of the other great apes, when the results are adjusted for size. Humans bite as hard as nutcrackers close, when size is taken into consideration.