I originally bought these tights for my daughter for Halloween and bought according to the size chart (my 11 year old daughter is barely a size 10). When she could barely put them on, I changed them up to the next size, which was supposed to fit a 14-year-old girl. They barely fit her well enough to wear for Halloween, but the crotch came halfway down to her knees and she spent a lot of time pulling her waist back up. I can't speak for all sizes but 8-10s. fit like 6 and 10-14 fit like 8.