I'm 5'5" and around 127 lbs, and I ordered sized XS and Small in Heather Grey. I am typically a Small in other brands, and I ended up keeping the size Small, so I would say it runs true to size, but that it is intended to be a relaxed/slightly oversized fit. In the size Small, it looked like it does... on the model - a slightly oversized, retro gym-class look. The only thing I would change about it is I wish there was *slightly* less material in the sleeve width, but it's not an issue for me. It reminds me a little bit of American Apparel unisex hoodies back in the day, but it is warmer and has more room at the hips. The XS did fit and was more a tailored look, which some may prefer, but the wrist cuffs and bottom around the hips were more snug than I liked (my hips around around 37"). The hoodie is incredibly soft both outside and inside. It is quite thick - I would describe it as medium to heavy weight. I'm super happy with it!