For women’s wigs, there are 3 basic sizes: Petite, Average and Large. Because most women wear an average sized cap (90- 95%), there will be more style-choices if your head size is average. For those who do not wear an Average, most of our ladies will wear a Large cap, and a few will wear a Small. Now you need to measure your head - the tape measure should be snug but not tight or pulled when the measurements are taken.