There is a drawstring inside the brim that allows one to adjust it. This cute hat fits my head just right and offers great sun protection. I was so grateful for the chin strap - it prevented the loss of the hat several times. The only problem was that the clips attaching the removable chin strap would snag on my hair; however, since I wore the hat on active outings, I didn't really care that it messed up my hairstyle.