Ring Size Conversion Chart
This script converts a selected ring size from any of the possible regions, to the ring size designation used in other count ries. Select any ONE ring size in the drop box selectors, any that are directly convertible will be shown in the region applicable. This is a very close approximation. .
USA size British French German Japanese Swiss
Diam. inch. Diam. mm Circum. mm

Printable Ring Sizer.
Jewelry A to Z realizes that you may not know the ring size for a given finger, and we want to help. We provide a printable ring sizer that can help you determine your ring size (click here).
How to determine your ring size.
The best size is usually the ring that fits snugly and gives a little resistance when you take it off. Wider rings should be a little looser that narrow rings. There are two common methods of reading a ring gauge, also called a sizing mandrel or sizing stick.
1. Wrap a piece of string or a strip of paper around your finger.
2. Mark the point where the two ends meet.
3. Measure the string or paper against a ruler to get the circumference of your finger.
4. You can enter that amount in the circumference box or divide it manually by PI (3.1417) to get the diameter of your finger.
5. Look up your ring size using the form above.

Ring Size Conversion Chart
Please note that these measurements are exact for the American system and approximate for the other sizing scales, since the intervals in each system do not correspond exactly.
Ring sizing gauges and finger gauges as well as published charts do not always agree. The ring sizing information presented here is the result of a conscientious study and comparison of various sources and is consistent with the instruments and measuring technique that we use in our workshop.

Inside Inside Inside Inside Number Sizes Wheat Sheaf    
Diameter Diameter Circumference Circumference US/Canada British Japanese Swiss
(inches) (mm) (inches) (mm) Standard Irish Equivalent Equivalent
       

 

Australian    
          Equivalent    
0.458 11.6 1.438 36.5 0      
0.466 11.8 1.463 37.2 1/4      
0.474 12.0 1.488 37.8 1/2 A    
0.482 12.2 1.513 38.4 3/4 A 1/2    
0.490 12.4 1.539 39.1 1 B 1  
0.498 12.6 1.564 39.7 1 1/4 B 1/2    
0.506 12.9 1.589 40.4 1 1/2 C    
0.514 13.1 1.614 41.0 1 3/4 C 1/2    
0.522 13.3 1.639 41.6 2 D 2 1.50
0.530 13.5 1.664 42.3 2 1/4 D 1/2    
0.538 13.7 1.689 42.9 2 1/2 E 3 2.75
0.546 13.9 1.714 43.5 2 3/4 E 1/2    
0.554 14.1 1.740 44.2 3 F 4 4.00
0.562 14.3 1.765 44.8 3 1/4 F 1/2 5 5.25
0.570 14.5 1.790 45.5 3 1/2 G    
0.578 14.7 1.815 46.1 3 3/4 G 1/2 6 6.50
0.586 14.9 1.840 46.7 4 7  
0.594 15.1 1.865 47.4 4 1/4 H 1/2   7.75
0.602 15.3 1.890 48.0 4 1/2 8  
0.610 15.5 1.915 48.7 4 3/4 J   9.00
0.618 15.7 1.941 49.3 5 J 1/2 9  
0.626 15.9 1.966 49.9 5 1/4 K   10.00
0.634 16.1 1.991 50.6 5 1/2 K 1/2 10  
0.642 16.3 2.016 51.2 5 3/4 L   11.75
0.650 16.5 2.041 51.8 6 L 1/2 11 12.75
0.658 16.7 2.066 52.5 6 1/4 12  
0.666 16.9 2.091 53.1 6 1/2 M 1/2 13 14.00
0.674 17.1 2.116 53.8 6 3/4 N    
0.682 17.3 2.141 54.4 7 N 1/2 14 15.25
0.690 17.5 2.167 55.0 7 1/4    
0.698 17.7 2.192 55.7 7 1/2 O 1/2 15 16.50
0.706 17.9 2.217 56.3 7 3/4    
0.714 18.1 2.242 56.9 8 P 1/2 16 17.75
0.722 18.3 2.267 57.6 8 1/4    
0.730 18.5 2.292 58.2 8 1/2 Q 1/2 17  
0.738 18.7 2.317 58.9 8 3/4 R   19
0.746 18.9 2.342 59.5 9 R 1/2 18  
0.754 19.2 2.368 60.1 9 1/4 S   20.25
0.762 19.4 2.393 60.8 9 1/2 S 1/2 19  
0.770 19.6 2.418 61.4 9 3/4 T   21.5
0.778 19.8 2.443 62.1 10 T 1/2 20  
0.786 20.0 2.468 62.7 10 1/4 U 21  
0.794 20.2 2.493 63.3 10 1/2 U 1/2 22 22.75
0.802 20.4 2.518 64.0 10 3/4 V    
0.810 20.6 2.543 64.6 11 V 1/2 23  
0.818 20.8 2.569 65.2 11 1/4 W   25
0.826 21.0 2.594 65.9 11 1/2 W 1/2 24  
0.834 21.2 2.619 66.5 11 3/4 X    
0.842 21.4 2.644 67.2 12 X 1/2 25 27.50
0.850 21.6 2.669 67.8 12 1/4    
0.858 21.8 2.694 68.4 12 1/2 Z 26 28.75
0.866 22.0 2.719 69.1 12 3/4 Z 1/2    
0.874 22.2 2.744 69.7 13   27  
0.882 22.4 2.769 70.3 13 1/4 Z1    
0.890 22.6 2.795 71.0 13 1/2      
0.898 22.8 2.820 71.6 13 3/4 Z2    
0.906 23.0 2.845 72.3 14 Z3    
0.914 23.2 2.870 72.9 14 1/4      
0.922 23.4 2.895 73.5 14 1/2 Z4    
0.930 23.6 2.920 74.2 14 3/4      
0.938 23.8 2.945 74.8 15      
0.946 24.0 2.970 75.4 15 1/4      
0.954 24.2 2.996 76.1 15 1/2      
0.962 24.4 3.021 76.7 15 3/4      
0.970 24.6 3.046 77.4 16