I ordered medium, but received small. I can't find this info on my orders to confirm if it's my fault or Amazons fault, but I'm pretty sure I ordered the media because I needed it. I bought these shirts from Walmart a few years ago and really liked them so I decided to find them on Amazon for my new job but this time in black. They're not as I originally remembered them, but they're still comfortable, soft, breathable, and stretchy. I hope they hold up just as well because I still have the ones I bought in June 2018. The seams on the shoulders look a bit different, there is a diagonal seam instead of a shoulder seam, but I'll probably keep the shorts as they stretch quite well. they still fit and my weight fluctuates. You probably need to order media for more relaxed work and I hope to send media next time. I will buy more of these as they are no longer available at Walmart and I love them but only if they send me the correct size.