Hello, size 37 1/3 in Adidas Hoops 3.0 K sneakers is larger than size 37. In shoe sizing, the “1/3” means that it is one third bigger than the exact size. So, a size 37 1/3 is a little bigger, not half a size bigger than a 37. Generally, according to the Adidas size chart, the approximate equivalents are as follows: Size 37 (EUR): Approximately corresponds to a foot length of 23 cm. Size 37 1/3 (EUR): Approximately corresponds to a foot length of 23.5 cm. Therefore, a size 37 1/3 is half a centimeter longer than a size 37.