I was not sure about my exact size.
Since I gained weight recently, I decided to get extra large pants but they were too big. I exchanged them to large ones but they were still loose. I exchanged them again to medium and they were right size for me. During the process, I could do everything online so easily. Although the exchange packages, they came with labels and nicely wrapped with papers exactly same as the first purchase. It did not cost me anything and the process was totally stress free.