US / Canada UK Europe  Length US (cm)  Length US (in.)
5.5 3 36 22.5 8 7/8
6 3.5 36.5 23 9
6.5 4 37.5 23.5 9 1/8
7 4.5 38 24 9 3/8
7.5 5 38.5 24.5 9 1/2
8 5.5 39 25 9 5/8
8.5 6 40 25.5 9 7/8