Ring size table

SURFACE MM EN US & CANADA UK
37.5 12 1/2 A
40.8 13 1 3/4 C 1/2
44.1 14 3 F
47.3 15 4 1/4 I
50.3 16 5 3/8 K 1/2
51.2 16.25 5 3/4 L 1/4
51.9 16.5 6 M
53.2 17 6 1/2 N
54.8 17.5 7 1/4 O 1/2
56.5 18 7 3/4 P 1/2
58.2 18.5 8 1/2 Q 3/4
60.0 19 9 1/8 S
60.4 19.25 9 1/4 S 1/4
61.3 19.5 9 5/8 T
62.9 20 10 1/4 U
63.5 20.25 10 1/2 U 1/2
64.2 20.5 10 3/4 V 1/4
65.8 21 11 3/8 W 1/2
67.5 21.5 12 Y