Ring Size Conversion Chart

SKD RING SIZE Inside Diameter in millimeters American Size
45.24 14.40 3 1/2
45.5 14.48
45.75 14.56 3 3/4
46 14.64
46.5 14.80 4    
47 14.96 4 1/4
47.5 15.10
47.73 15.20 4 1/2
48 15.30
48.5 15.44 4 3/4
49 15.60 5    
49.5 15.76 5 1/4
50 15.90
50.24 16.00 5 1/2
50.5 16.10
51 16.23 5 3/4
51.5 16.39 6    
52 16.55 6 1/4
52.5 16.70
52.75 16.80 6 1/2
53 16.90
53.5 17.03 6 3/4
54 17.19 7    
54.5 17.30
54.64 17.40 7 1/4
55 17.50
55.26 17.60 7 1/2
55.5 17.70
56 17.83 7 3/4
56.5 17.99 8    
57 18.10
57.15 18.20 8 1/4
57.5 18.30
57.78 18.40 8 1/2
58 18.50
58.5 18.62 8 3/4
59 18.78 9    
59.5 18.90
59.66 19.00 9 1/4
60 19.10
60.29 19.20 9 1/2
60.5 19.30
61 19.42 9 3/4
61.5 19.58 10    
62 19.70
62.17 19.80 10 1/4
62.8 20.00 10 1/2
63 20.05
63.43 20.20 10 3/4
64 20.37 11    
64.68 20.60 11 1/4
65 20.70
65.3 20.80 11 1/2
66 21.01 11 3/4
66.57 21.20 12    
67.2 21.40 12 1/4
67.82 21.60 12 1/2
68.45 21.80 12 3/4
69.1 22.00 13    
Ring Size Conversion Chart
SKD RING SIZE Inside Diameter in millimeters American Size
45.24 14.40 3 1/2
45.5 14.48
45.75 14.56 3 3/4
46 14.64
46.5 14.80 4    
47 14.96 4 1/4
47.5 15.10
47.73 15.20 4 1/2
48 15.30
48.5 15.44 4 3/4
49 15.60 5    
49.5 15.76 5 1/4
50 15.90
50.24 16.00 5 1/2
50.5 16.10
51 16.23 5 3/4
51.5 16.39 6    
52 16.55 6 1/4
52.5 16.70
52.75 16.80 6 1/2
53 16.90
53.5 17.03 6 3/4
54 17.19 7    
54.5 17.30
54.64 17.40 7 1/4
55 17.50
55.26 17.60 7 1/2
55.5 17.70
56 17.83 7 3/4
56.5 17.99 8    
57 18.10
57.15 18.20 8 1/4
57.5 18.30
57.78 18.40 8 1/2
58 18.50
58.5 18.62 8 3/4
59 18.78 9    
59.5 18.90
59.66 19.00 9 1/4
60 19.10
60.29 19.20 9 1/2
60.5 19.30
61 19.42 9 3/4
61.5 19.58 10    
62 19.70
62.17 19.80 10 1/4
62.8 20.00 10 1/2
63 20.05
63.43 20.20 10 3/4
64 20.37 11    
64.68 20.60 11 1/4
65 20.70
65.3 20.80 11 1/2
66 21.01 11 3/4
66.57 21.20 12    
67.2 21.40 12 1/4
67.82 21.60 12 1/2
68.45 21.80 12 3/4
69.1 22.00 13