International Size Guide
Conversion Chart For Ring Size | |||||||
Sizes | Inside Diameter | Inside Circumference | |||||
United States and Canada | UK, Ireland, Australia, and New Zealand | India, China, Japan, South America | Italy, Spain, Netherlands, Switzerland |
(in) | (mm) | (in) | (mm) |
0 | 0.458 | 11.63 | 1.44 | 36.5 | |||
1/4 | 0.466 | 11.84 | 1.46 | 37.2 | |||
1/2 | A | 0.474 | 12.04 | 1.49 | 37.8 | ||
3/4 | A 1/2 | 0.482 | 12.24 | 1.51 | 38.5 | ||
1 | B | 0.49 | 12.45 | 1.54 | 39.1 | ||
1 1/4 | B 1/2 | 1 | 0.498 | 12.65 | 1.56 | 39.7 | |
1 1/2 | C | 0.5 | 0.506 | 12.85 | 1.59 | 40.4 | |
1 3/4 | C 1/2 | 1 | 0.514 | 13.06 | 1.61 | 41.0 | |
2 | D | 2 | 1.75 | 0.522 | 13.26 | 1.64 | 41.7 |
2 1/4 | D 1/2 | 2.25 | 0.53 | 13.46 | 1.67 | 42.3 | |
2 1/2 | E | 3 | 3 | 0.538 | 13.67 | 1.69 | 42.9 |
2 3/4 | E 1/2 | 3.5 | 0.546 | 13.87 | 1.72 | 43.6 | |
3 | F | 4 | 4.25 | 0.554 | 14.07 | 1.74 | 44.2 |
3 1/4 | F 1/2 | 5 | 4.75 | 0.562 | 14.27 | 1.77 | 44.8 |
3 1/2 | G | 5.5 | 0.57 | 14.48 | 1.79 | 45.5 | |
3 3/4 | G 1/2 | 6 | 6 | 0.578 | 14.68 | 1.82 | 46.1 |
4 | H | 7 | 6.75 | 0.586 | 14.88 | 1.84 | 46.8 |
4 1/4 | H 1/2 | 7.5 | 0.594 | 15.09 | 1.87 | 47.4 | |
4 1/2 | I | 8 | 8 | 0.602 | 15.29 | 1.89 | 48.0 |
4 3/4 | J | 8.75 | 0.61 | 15.49 | 1.92 | 48.7 | |
5 | J 1/2 | 9 | 9.25 | 0.618 | 15.70 | 1.94 | 49.3 |
5 1/4 | K | 10 | 0.626 | 15.90 | 1.97 | 50.0 | |
5 1/2 | K 1/2 | 10 | 10.5 | 0.634 | 16.10 | 1.99 | 50.6 |
5 3/4 | L | 11.25 | 0.642 | 16.31 | 2.02 | 51.2 | |
6 | L 1/2 | 11 | 11.75 | 0.65 | 16.51 | 2.04 | 51.9 |
6 1/4 | M | 12 | 12.5 | 0.658 | 16.71 | 2.07 | 52.5 |
6 1/2 | M 1/2 | 13 | 13.25 | 0.666 | 16.92 | 2.09 | 53.1 |
6 3/4 | N | 13.75 | 0.674 | 17.12 | 2.12 | 53.8 | |
7 | N 1/2 | 14 | 14.5 | 0.682 | 17.32 | 2.14 | 54.4 |
7 1/4 | O | 15 | 0.69 | 17.53 | 2.17 | 55.1 | |
7 1/2 | O 1/2 | 15 | 15.75 | 0.698 | 17.73 | 2.19 | 55.7 |
7 3/4 | P | 16.25 | 0.706 | 17.93 | 2.22 | 56.3 | |
8 | P 1/2 | 16 | 17 | 0.714 | 18.14 | 2.24 | 57.0 |
8 1/4 | Q | 17.5 | 0.722 | 18.34 | 2.27 | 57.6 | |
8 1/2 | Q 1/2 | 17 | 18.25 | 0.73 | 18.54 | 2.29 | 58.3 |
8 3/4 | R | 19 | 0.738 | 18.75 | 2.32 | 58.9 | |
9 | R 1/2 | 18 | 19.5 | 0.746 | 18.95 | 2.34 | 59.5 |
9 1/4 | S | 20.25 | 0.754 | 19.15 | 2.37 | 60.2 | |
9 1/2 | S 1/2 | 19 | 20.75 | 0.762 | 19.35 | 2.39 | 60.8 |
9 3/4 | T | 21.5 | 0.77 | 19.56 | 2.42 | 61.4 | |
10 | T 1/2 | 20 | 22 | 0.778 | 19.76 | 2.44 | 62.1 |
10 1/4 | U | 21 | 22.75 | 0.786 | 19.96 | 2.47 | 62.7 |
10 1/2 | U 1/2 | 22 | 23.25 | 0.794 | 20.17 | 2.49 | 63.4 |
10 3/4 | V 1/2 | 24 | 0.802 | 20.37 | 2.52 | 64.0 | |
11 | V 1/2 | 23 | 24.75 | 0.81 | 20.57 | 2.54 | 64.6 |
11 1/4 | W 1/2 | 25.25 | 0.818 | 20.78 | 2.57 | 65.3 | |
11 1/2 | W 1/2 | 24 | 26 | 0.826 | 20.98 | 2.59 | 65.9 |
11 3/4 | X | 26.5 | 0.834 | 21.18 | 2.62 | 66.6 | |
12 | X 1/2 | 25 | 27.25 | 0.842 | 21.39 | 2.65 | 67.2 |
12 1/4 | Y | 27.75 | 0.85 | 21.59 | 2.67 | 67.8 | |
12 1/2 | Z | 26 | 28.5 | 0.858 | 21.79 | 2.70 | 68.5 |
12 3/4 | Z 1/2 | 29 | 0.866 | 22.00 | 2.72 | 69.1 | |
13 | 27 | 29.75 | 0.874 | 22.20 | 2.75 | 69.7 | |
13 1/4 | Z1 | 30.5 | 0.882 | 22.40 | 2.77 | 70.4 | |
13 1/2 | 31 | 0.89 | 22.61 | 2.80 | 71.0 | ||
13 3/4 | Z2 | 31.75 | 0.898 | 22.81 | 2.82 | 71.7 | |
14 | Z3 | 32.25 | 0.906 | 23.01 | 2.85 | 72.3 | |
14 1/4 | 33 | 0.914 | 23.22 | 2.87 | 72.9 | ||
14 1/2 | Z4 | 33.5 | 0.922 | 23.42 | 2.90 | 73.6 | |
14 3/4 | 34.25 | 0.93 | 23.62 | 2.92 | 74.2 | ||
15 | 34.75 | 0.938 | 23.83 | 2.95 | 74.8 | ||
15 1/4 | 35.5 | 0.946 | 24.03 | 2.97 | 75.5 | ||
15 1/2 | 36.25 | 0.954 | 24.23 | 3.00 | 76.1 | ||
15 3/4 | 36.75 | 0.962 | 24.43 | 3.02 | 76.8 | ||
16 | 37.5 | 0.97 | 24.64 | 3.05 | 77.4 |