The sweatshirt is regular sweatshirt thickness. I was worried that it would be thin since it seems a lot of sweatshirts are on Amazon, but it is a traditional sweatshirt. I bought the large for my average sized 8 yr old son because I wanted room to grow. The sleeves and body have extra length, which means it should last at least another year or two, but it doesn't look silly big on him. He loves it and says it's soft inside. Also very happy with the price.