The official Yeezy Supply page explicitly tells you to order a half size up. Does that mean that's the canon sizing and not just a thing everyone decided to do? : r/yeezys
A full Size Guide for Every Yeezy Model - Yeezy 350, 500s, 700s and more!
Size Charts (adidas Yeezy) | FLEXDOG
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The Ultimate Yeezy 350 Sizing and Fit Guide - Farfetch