Ring Sizer

Inside Diameter  Sizes
MM Inches British & Australian  US & Canada
14.36 0.565 G 3 3/8
14.56 0.573 G 1/2 3 5/8
14.65 0.577 H 3 3/4
14.86 0.585 H 1/2 4
15.04 0.592 I 4 1/4
15.27 0.601 I 1/2 4 1/2
15.40 0.606 J 4 5/8
15.70 0.618 J 1/2 5
15.80 0.622 K 5 1/8
16.00 0.630 K 1/2 5 3/8
16.10 0.634 L 5 1/2
16.41 0.646 L 1/2 5 7/8
16.51 0.650 M 6
16.71 0.658 M 1/2 6 1/4
16.92 0.666 N 6 1/2
17.13 0.674 N 1/2 6 3/4
17.35 0.683 O 7
17.45 0.687 O 1/2 7 1/4
17.75 0.699 P 7 1/2
17.97 0.707 P 1/2 7 3/4
18.19 0.716 Q 8
18.35 0.722 Q 1/2 8 1/4
18.61 0.733 R 8 5/8
18.80 0.740 R 1/2 8 7/8
19.10 0.752 S 9 1/8
19.31 0.760 S 1/2 9 3/8
19.51 0.768 T 9 5/8
19.84 0.781 T 1/2 10
20.02 0.788 U 10 1/4
20.20 0.797 U 1/2 10 1/2
20.32 0.800 V 10 5/8
20.68 0.814 V 1/2 11