Most manufacturers identify cap sizes differently. Use this guide to help identify the capsize circumference of a wig. To find your cap size for a wig or hairpiece, use a flexible fabric or plastic tape measure and place one end in the middle of your forehead (just touching your front hairline), then wrap the remaining tape around the back of your your head just above your neck hairline behind your ears and then back to the middle of your forehead. Take this measurement and use the below chart to help select the correct size for your cap!