I would say sizes run
"I would say sizes run small. I wear a XL in t shirts at Goodwear but should have gotten this in a 2xl, still fits but too tight to wear it alone have to have a shirt over it. (think 1984 flannel over T look). That being said it is comfortable stretchable when you put it on and it feels nice. It did come with sort of a gasoline scent to it reminiscent of everything from Temu, I state that just as a note maybe it's a new plastic bag Goodwear is using for shipping. By no means was this any sort of a jab at the quality and comfort that has made me a life long Goodwear customer (or at least for the 20 years im hoping are still in the tank)."