For Women

EU US UK
34 4 2
35 5 2,5
36 5,5 3,5
37 6,5 4
38 7,5 5
39 8,5 5,5
40 9 6,5
41 10 7,5
42 11 8
43 12 9

For Kids

EU US UK
15 B0 B0
16 B1 B1
17 B2 B1,5
18 B3 B2
19 K4 K3
20 K5 K4
21 K5.5 K4,5
22 K6 K5,5
23 K7 K6
24 K8 K7
25 K9 K8
26 K9.5 K8,5
27 K10.5 K9,5
28 K11 K10
29 K11.5 K11
30 K12 K11,5
31 K13 K12,5
32 K1 K13,5
33 K2 1

Note: If you’re undecided between 2 sizes, always choose the larger size.