Ring Sizes

Inside Diameter  Inside Circumference Sizes
MM MM British US
9.91 31.13 - 0000
10.72 33.68 - 00
11.53 36.22 - 0
11.95 37.54 A 1/2
12.18 38.26 A 1/2 3/4
12.37 38.86 B 1
12.60 39.58 B 1/2 1 1/4
12.78 40.15 C 1 1/2
13.00 40.84 C 1/2 1 3/4
13.21 41.50 D 2
13.41 42.13 D 1/2 2 1/4
13.61 42.76 E 2 1/2
13.83 43.45 E 1/2 2 3/4
14.05 44.14 F 3
14.15 44.45 F 1/2 3 1/8
14.25 44.77 F 3/4 3 1/4
14.36 45.11 G 3 3/8
14.45 45.40 G 1/4 3 1/2
14.56 45.74 G 1/2 3 5/8
14.65 46.02 H 3 3/4
14.86 46.68 H 1/2 4
15.04 47.25 I 4 1/4
15.27 47.97 I 1/2 4 1/2
15.40 48.38 J 4 5/8
15.53 48.79 J 1/4 4 3/4
15.70 49.32 J 1/2 5
15.80 49.64 K 5 1/8
15.90 49.95 K 1/4 5 1/4
16.00 50.27 K 1/2 5 3/8
16.10 50.58 L 5 1/2
16.30 51.21 L 1/4 5 3/4
16.41 51.55 L 1/2 5 7/8
16.51 51.87 M 6
16.71 52.50 M 1/2 6 1/4
16.92 53.16 N 6 1/2
17.13 53.82 N 1/2 6 3/4
17.35 54.51 O 7
17.45 54.82 O 1/2 7 1/4
17.75 55.76 P 7 1/2
17.97 56.45 P 1/2 7 3/4
18.19 57.15 Q 8
18.35 57.65 Q 1/2 8 1/4
18.53 58.21 Q 3/4 8 1/2
18.61 58.47 R 8 5/8
18.69 58.72 R 1/4 8 3/4
18.80 59.06 R 1/2 8 7/8
18.89 59.34 R 3/4 9
19.10 60.00 S 9 1/8
19.22 60.38 S 1/4 9 1/4
19.31 60.66 S 1/2 9 3/8
19.41 60.98 S 3/4 9 1/2
19.51 61.29 T 9 5/8
19.62 61.64 T 1/4 9 3/4
19.84 62.33 T 1/2 10
20.02 62.89 U 10 1/4
20.20 63.46 U 1/2 10 1/2
20.32 63.84 V 10 5/8
20.44 64.21 V 1/4 10 3/4
20.68 64.97 V 1/2 11
20.76 65.22 W 11 1/8
20.85 65.50 W 1/4 11 1/4
20.94 65.78 W 1/2 11 3/8
21.08 66.22 W 3/4 11 1/2
21.18 66.54 X 11 5/8
21.24 66.73 X 1/4 11 3/4
21.30 66.92 X 1/2 11 7/8
21.49 67.51 Y 12
21.69 68.14 Y 1/2 12 1/4
21.89 68.77 Z 12 1/2
22.10 69.43 Z +1/2 12 3/4
22.33 70.15 Z+1 13
22.60 71.00 Z+1.5 13.5
22.69 71.28 Z+2 -
22.92 72.00 Z+2.5 -
23.06 72.45 Z+3 -
23.24 73.01 Z+3.5 -
23.47 73.73 Z+4 -
23.55 73.98 Z+4.5 -
23.87 74.99 Z+5 -
24.27 76.25 Z+6 -