Women have smaller feet than men due to the fact that, in general, women have smaller joints and bones than their male counterparts. Based on this information, it is no surprise that women also have smaller ankles, knees, wrists and other major joints, explains The Register.
Women even have some smaller internal organs, including the kidneys, the heart, the lungs and even the brain. One of the most likely primary reasons women have smaller feet than men is that a woman's legs only make up 51 percent of her total height, whereas a man's legs make up 56 percent of his height. Since the human body is designed to provide maximum balance, it makes sense that women have smaller feet than men if their legs make up less than their total height; after all, feet are designed to work together with the rest of the body to assist in moving and standing.
Yet another factor that helps explain why women's feet may be smaller than men's lies in the fact that foot position is dictated by the hip and knee. As women have smaller knee joints and wider hips than men, it makes sense that a woman's foot is smaller.