Wigs are generally available in 4 sizes:

• Ultra Petite - Fits heads 19" - 20"
• Petite - Fits heads 20" - 21"
• Average - Fits heads 21 1/2" - 22 1/2"
• Large - Fits heads 22 1/2" - 24"

(90% of all women fall into the Average size range.)

Some wig companies, such as Eva Gabor and Raquel Welch, have sizes like "Petite Average" and "Average Large." This is simply another way of saying "Petite" and "Large," while noting that there is some overlap among sizes.

Wig caps are adjustable. By adjusting the elastic straps, you can make the cap tighter or looser.

To measure the circumference of your head for a wig, take the tape measure and place it at the middle of your forehead at the hairline. Then run the tape around the head, behind one ear, around the nape of the neck, behind the other ear, then back to the front at the hairline.