Ring Size Chart

Inside diameter Inside circumference Sizes
(in) (mm) (in) (mm) United States
and Canada
United Kingdom,
Ireland,
and Australia
China,
Japan
Switzerland
0.459 11.63 1.44 36.5 0      
0.466 11.84 1.46 37.2 ¼      
0.474 12.04 1.49 37.8 ½ A    
0.482 12.24 1.51 38.5 ¾    
0.490 12.45 1.54 39.1 1 B 1  
0.498 12.65 1.56 39.7    
0.506 12.85 1.59 40.4 C    
0.514 13.06 1.61 41.0    
0.522 13.26 1.64 41.7 2 D 2 1.5
0.530 13.46 1.67 42.3    
0.538 13.67 1.69 42.9 E 3 2.75
0.546 13.87 1.72 43.6    
0.554 14.07 1.74 44.2 3 F 4 4
0.562 14.27 1.77 44.8 5 5.25
0.570 14.48 1.79 45.5 G    
0.578 14.68 1.82 46.1 6 6.5
0.586 14.88 1.84 46.8 4 H 7  
0.594 15.09 1.87 47.4   7.75
0.602 15.29 1.89 48.0 I 8  
0.610 15.49 1.92 48.7 J   9
0.618 15.70 1.94 49.3 5 9  
0.626 15.90 1.97 50.0 K   10
Inside diameter Inside circumference Sizes
(in) (mm) (in) (mm) United States
and Canada
United Kingdom,
Ireland,
and Australia
China,
Japan
Switzerland
0.634 16.10 1.99 50.6 10  
0.642 16.31 2.02 51.2 L   11.75
0.650 16.51 2.04 51.9 6 11 12.75
0.658 16.71 2.07 52.5 M 12  
0.666 16.92 2.09 53.1 13 14
0.674 17.12 2.12 53.8 N    
0.682 17.32 2.14 54.4 7 14 15.25
0.690 17.53 2.17 55.1 O    
0.698 17.73 2.19 55.7 15 16.5
0.706 17.93 2.22 56.3 P    
0.714 18.14 2.24 57.0 8 16 17.75
0.722 18.34 2.27 57.6 Q    
0.730 18.54 2.29 58.3 17  
0.738 18.75 2.32 58.9 R   19
0.746 18.95 2.34 59.5 9 18  
0.754 19.15 2.37 60.2 S   20.25
0.762 19.35 2.39 60.8 19  
0.770 19.56 2.42 61.4 T   21.5
0.778 19.76 2.44 62.1 10 20  
0.786 19.96 2.47 62.7 10¼ U 21  
0.794 20.17 2.49 63.4 10½ 22 22.75
0.802 20.37 2.52 64.0 10¾ V    
Inside diameter Inside circumference Sizes
(in) (mm) (in) (mm) United States
and Canada
United Kingdom,
Ireland,
and Australia
China,
Japan
Switzerland
0.810 20.57 2.54 64.6 11 23  
0.818 20.78 2.57 65.3 11¼ W   25
0.826 20.98 2.59 65.9 11½ 24  
0.834 21.18 2.62 66.6 11¾ X    
0.842 21.39 2.65 67.2 12 25 27.5
0.850 21.59 2.67 67.8 12¼ Y    
0.858 21.79 2.70 68.5 12½ Z 26 28.75
0.866 22.00 2.72 69.1 12¾    
0.874 22.20 2.75 69.7 13   27  
0.882 22.40 2.77 70.4 13¼ Z1    
0.890 22.61 2.80 71.0 13½      
0.898 22.81 2.82 71.7 13¾ Z2    
0.906 23.01 2.85 72.3 14 Z3    
0.914 23.22 2.87 72.9 14¼      
0.922 23.42 2.90 73.6 14½ Z4    
0.930 23.62 2.92 74.2 14¾      
0.938 23.83 2.95 74.8 15      
0.946 24.03 2.97 75.5 15¼      
0.954 24.23 3.00 76.1 15½      
0.962 24.43 3.02 76.8 15¾      
0.970 24.64 3.05 77.4 16