Shein vs AliExpress Sizing

Both Shein and AliExpress ship from Asian manufacturers, but their sizing conventions differ noticeably. AliExpress generally runs the smallest of all Asian marketplaces — often two or more sizes below US standards — while Shein runs about one to two sizes small. This difference exists because AliExpress sellers often use pure Chinese sizing, while Shein has adapted their charts slightly toward Western expectations. For a US women's Medium, you might need an XL on Shein but a 2XL or 3XL on AliExpress. Shoes are more comparable between the two platforms, though AliExpress shoes tend to be slightly narrower. Our converter shows your size at both stores side by side so you can see the differences across tops, jeans, shoes and swimwear.