I bought this hat for my husband as a b-day gift.  He doesn't have a larger than normal head, or overly thick hair, but when he tried it on it was almost comical how small it was.  The circumference was fine, but the sides were no where near his ears - probably about 3 inches above.  It looked ridiculous.  We gave it to our 15 year old son, who is on the small side, and it fit him fine.