How to measure ring size

1. Cut a strip of paper or a piece of string. The paper should be no wider than 3/4" (2 cm) and at least 4" (10 cm) long.

 

2. Wrap the paper or string around the base of the finger to be sized. Make sure the measurement is snug, but not too tight.

 

3. Mark the string or paper where it completes the circle.

 

4. Take the length of the paper or string measurement. Measure from the beginning to the mark with a ruler or tape measure.

 

Find the measurement on the chart below to find the corresponding ring size.

 

US/Canada
Ring sizes 		Inner
Diameter 		Inner
Diameter 		Inner
Circumference 		Inner
Circumference 		British,
Irish,
Australian
sizes 		Japanese
sizes 		Swiss/Italy/
Spain/
Netherlands
sizes
Standard (inches) (mm) (inches) (mm) Equivalent Equivalent Equivalent
0 0.458 11.6 1.438 36.5      
1/4 0.466 11.8 1.463 37.2      
1/2 0.474 12.0 1.488 37.8 A    
3/4 0.482 12.2 1.513 38.4 A 1/2    
1 0.490 12.4 1.539 39.1 B 1  
1 1/4 0.498 12.6 1.564 39.7 B 1/2    
1 1/2 0.506 12.9 1.589 40.4 C    
1 3/4 0.514 13.1 1.614 41.0 C 1/2    
2 0.522 13.3 1.639 41.6 D 2 1.50
2 1/4 0.530 13.5 1.664 42.3 D 1/2    
2 1/2 0.538 13.7 1.689 42.9 E 3 2.75
2 3/4 0.546 13.9 1.714 43.5 E 1/2    
3 0.554 14.1 1.740 44.2 F 4 4.00
3 1/4 0.562 14.3 1.765 44.8 F 1/2 5 5.25
3 1/2 0.570 14.5 1.790 45.5 G    
3 3/4 0.578 14.7 1.815 46.1 G 1/2 6 6.50
4 0.586 14.9 1.840 46.7 H  7  
4 1/4 0.594 15.1 1.865 47.4 H 1/2   7.75
4 1/2 0.602 15.3 1.890 48.0 I  8  
4 3/4 0.610 15.5 1.915 48.7 J   9.00
5 0.618 15.7 1.941 49.3 J 1/2 9  
5 1/4 0.626 15.9 1.966 49.9 K   10.00
5 1/2 0.634 16.1 1.991 50.6 K 1/2 10  
5 3/4 0.642 16.3 2.016 51.2 L   11.75
6 0.650 16.5 2.041 51.8 L 1/2 11 12.75
6 1/4 0.658 16.7 2.066 52.5 M  12  
6 1/2 0.666 16.9 2.091 53.1 M 1/2 13 14.00
6 3/4 0.674 17.1 2.116 53.8 N    
7 0.682 17.3 2.141 54.4 N 1/2 14 15.25
7 1/4 0.690 17.5 2.167 55.0 O     
7 1/2 0.698 17.7 2.192 55.7 O 1/2 15 16.50
7 3/4 0.706 17.9 2.217 56.3 P     
8 0.714 18.1 2.242 56.9 P 1/2 16 17.75
8 1/4 0.722 18.3 2.267 57.6 Q     
8 1/2 0.730 18.5 2.292 58.2 Q 1/2 17  
8 3/4 0.738 18.7 2.317 58.9 R   19
9 0.746 18.9 2.342 59.5 R 1/2 18  
9 1/4 0.754 19.2 2.368 60.1 S   20.25
9 1/2 0.762 19.4 2.393 60.8 S 1/2 19  
9 3/4 0.770 19.6 2.418 61.4 T   21.5
10 0.778 19.8 2.443 62.1 T 1/2 20  
10 1/4 0.786 20.0 2.468 62.7 U 21  
10 1/2 0.794 20.2 2.493 63.3 U 1/2 22 22.75
10 3/4 0.802 20.4 2.518 64.0 V    
11 0.810 20.6 2.543 64.6 V 1/2 23  
11 1/4 0.818 20.8 2.569 65.2 W   25
11 1/2 0.826 21.0 2.594 65.9 W 1/2 24  
11 3/4 0.834 21.2 2.619 66.5 X    
12 0.842 21.4 2.644 67.2 X 1/2 25 27.50
12 1/4 0.850 21.6 2.669 67.8 Y     
12 1/2 0.858 21.8 2.694 68.4 Z 26 28.75
12 3/4 0.866 22.0 2.719 69.1 Z 1/2    
13 0.874 22.2 2.744 69.7   27  
13 1/4 0.882 22.4 2.769 70.3 Z1    
13 1/2 0.890 22.6 2.795 71.0      
13 3/4 0.898 22.8 2.820 71.6 Z2    
14 0.906 23.0 2.845 72.3 Z3    
14 1/4 0.914 23.2 2.870 72.9      
14 1/2 0.922 23.4 2.895 73.5 Z4    
14 3/4 0.930 23.6 2.920 74.2      
15 0.938 23.8 2.945 74.8 Z5    
15 1/4 0.946 24.0 2.970 75.4      
15 1/2 0.954 24.2 2.996 76.1      
15 3/4 0.962 24.4 3.021 76.7 Z6    
16 0.970 24.6 3.046 77.4      

Special notes:
There are several systems for denoting the sizes of jewellery rings in use around the world: The ISO standard for ring sizes is ISO 8653:1986, which defines standard ring sizes in terms of the inner circumference of the ring measured in millimetres.
- In the United States and Canada, ring sizes are specified using a numerical scale, with quarter and half sizes. An increase of a full size is an increase of 0.032 inch (0.8128 mm) in diameter, or roughly 1/10 inch (more precisely, 0.1005 in or 2.55 mm) in inside circumference. 
- In Ireland, the United Kingdom and Australia, ring sizes are specified using an alphabetical scale, with half sizes.
- In India, Japan and China, ring sizes are specified using a numerical scale, that only has whole sizes, and does not have simple linear correlation with diameter or circumference. 
- In Austria, France, Germany, Belgium and Scandinavia, ring sizes are specified using actual internal circumference in mm (the same as the ISO standard).
- In Italy, Spain, Netherlands, and Switzerland, ring sizes are specified as the circumference minus 40mm. A 50 in Germany will be a 10 in Switzerland.