I sized up based on reviews saying it runs small and it must. While I have room in it, it fits exactly as it should and I would want it to. The whole point of this style is for it to have a relaxed look, effortlessly covering your arms, not tight. If I had bought my size, it would probably look tight, even though the denim has some give. The sleeves are long enough, even when reaching/raising arms. The buttons button and lay down over/on top of my chest. Literally, it fits exactly like the model, but I sized up 2 sizes, from 1x to 3x, to be safe. I'm 5'9', 260, hourglass, and fit most FN stuff as 1x. If you can do it, get it