Use the size chart to determine your ring size.

US Size UK Size Diameter (mm) Circumference (mm)
4 H 14.8 46.5
5 J 15.7 49.3
6 L 16.5 51.8
7 N 17.3 54.4
8 P 18.1 57.0
9 R 19.0 59.5
10 T 19.8 62.1
11 V 20.6 64.6
12 X 21.4 67.2