I usually wear a large or 1X, but ordered a 2X as I intended just to wear it around the house on hot days. Even with being that much larger, I am impressed that the armholes don't show a thing! Will be ordering more in my size as these are a nice weight and look for wearing out and about.  (I'm 5'3", 140lbs, 40C) I'll go with the 1X.  If you wear a tank underneath, you might want to go up one from your regular size to give you room. Color is as pictured, it is not see through and is very comfortable.