Question: is 20w the same as 1x?
Answer: 1X is larger then XL. This is because L, XL, XXL are all in misses/womens sizing. 1X, 2X, 3X are all in women's PLUS sized sizing. So in this case 1X or 2X (being PLUS size garments for heavier set women) are going to be larger then an XL, XXL in regular misses sizes.