Calculate your wig size by measuring the circumference around the hairline. Most of the time, you only need the circumference measurement of your head to get the accurate indication of your cap size. However, if your recommended size did not meet your expectations or you are looking for a custom wig, you may also need to take your ear to ear and front to back measurements as well. TRS Care offers Child, Petite, Petite/Average, Average, Average/Large, and Large cap size wigs.