These socks will fit a wide range of sizes thanks to the elasticity of the ribbing! They are graded to fit an approx. foot circumference of: 4.5 (5.5, 6, 6.5, 7)(7, 8, 9)[8, 9, 10]”/11.5 (14, 15, 16.5, 18)(18, 20.5, 23)[20.5, 23, 25.5] cm worn with approx 0.25-1”/1-2.5 cm of negative ease (less for the smaller sizes, and more for the larger sizes).