For the perfect fit: Take a ring that fits you well and measure its internal diameter (mm). Use our chart to figure out your perfect ring size.
Internal Diameter (mm) US/Canada Ring Size UK/AU Ring Size
14.07 3 F
14.48 3.5 G
14.88 4 H
15.29 4.5 I
15.7 5 J
16.1 5.5 K 1/2
16.51 6 L 1/2
16.92 6.5 M 1/2
17.32 7 N 1/2
17.73 7.5 O 1/2
18.14 8 P 1/2
18.54 8.5 Q 1/2
18.95 9 R 1/2
19.35 9.5 S 1/2
19.76 10 T 1/2
20.17 10.5 U 1/2
20.57 11 V 1/2
20.98 11.5 W 1/2
21.39 12 X 1/2