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)
Ring Size Inner Diameter Inner Circumference
(mm) (mm)
(mm) (mm)
0 11.6 36.5
¼ (0.25) 11.8 37.2
½ (0.5) 12.0 37.8
¾ (0.75) 12.2 38.4
1 12.4 39.1
1 ¼ (1.25) 12.6 39.7
1 ½ (1.5) 12.9 40.4
1 ¾ (1.75) 13.1 41.0
2 13.3 41.6
2 ¼ (2.25) 13.5 42.3
2 ½ (2.5) 13.7 42.9
2 ¾ (2.75) 13.9 43.5
3 14.1 44.2
3 ¼ (3.25) 14.3 44.8
3 ½ (3.5) 14.5 45.5
3 ¾ (3.75) 14.7 46.1
4 14.9 46.7
4 ¼ (4.25) 15.1 47.4
4 ½ (4.5) 15.3 48.0
4 ¾ (4.75) 15.5 48.7
5 15.7 49.3
5 ¼ (5.25) 15.9 49.9
5 ½ (5.5) 16.1 50.6
5 ¾ (5.75) 16.3 51.2
6 16.5 51.8
6 ¼ (6.25) 16.7 52.5
6 ½ (6.5) 16.9 53.1
6 ¾ (6.75) 17.1 53.8
7 17.3 54.4
7 ¼ (7.25) 17.5 55.0
7 ½ (7.5) 17.7 55.7
7 ¾ (7.75) 17.9 56.3
8 18.1 56.9
8 ¼ (8.25) 18.3 57.6
8 ½ (8.5) 18.5 58.2
8 ¾ (8.75) 18.7 58.9
9 18.9 59.5
9 ¼ (9.25) 19.2 60.1
9 ½ (9.5) 19.4 60.8
9 ¾ (9.75) 19.6 61.4
10 19.8 62.1
10 ¼ (10.25) 20.0 62.7
10 ½ (10.5) 20.2 63.3
10 ¾ (10.75) 20.4 64.0
11 20.6 64.6
11 ¼ (11.25) 20.8 65.2
11 ½ (11.5) 21.0 65.9
11 ¾ (11.75) 21.2 66.5
12 21.4 67.2
12 ¼ (12.25) 21.6 67.8
12 ½ (12.5) 21.8 68.4
12 ¾ (12.75) 22.0 69.1
13 22.2 69.7
13 ¼ (13.25) 22.4 70.3
13 ½ (13.5) 22.6 71.0
13 ¾ (13.75) 22.8 71.6
14 23.0 72.3
14 ¼ (14.25) 23.2 72.9
14 ½ (14.5) 23.4 73.5
14 ¾ (14.75) 23.6 74.2
15 23.8 74.8
15 ¼ (15.25) 24.0 75.4
15 ½ (15.5) 24.2 76.1
15 ¾ (15.75) 24.4 76.7
16 24.6 77.4
Click here for a guide to UK Ring Sizes & Measurements
Guide created: 10/12/08 (updated 10/12/08)
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