My recommended size is small, and I own this shirt in small. This one was way too small. Pit to pit was a full 3” less than the one I already own. The sleeves were also too tight for my arms to fit and I can wrap my fingers around my wrist. I saw reviews where some ppl even recommended sizing down, so I really don’t get it. I typically wear a size small, but I was even nervous that a medium still might not fit, so I just returned mine. There is also zero stretch and it just felt so stiff and scratchy. I don’t know if that would get better after washing. I like the look though!