rings size conversion chart
US SIZE | UK SIZE | INSIDE DIA IN | INSIDE DIA MM | INSIDE CIRC IN | INSIDE CIRC MM |
---|---|---|---|---|---|
1/2 | A | 0.474 | 12.0 | 1.488 | 37.8 |
3/4 | A 1/2 | 0.482 | 12.2 | 1.513 | 38.4 |
1 | B | 0.490 | 12.4 | 1.539 | 39.1 |
1 1/4 | B 1/2 | 0.498 | 12.6 | 1.564 | 39.7 |
1 1/2 | C | 0.506 | 12.9 | 1.589 | 40.4 |
1 3/4 | C 1/2 | 0.514 | 13.1 | 1.614 | 41.0 |
2 | D | 0.522 | 13.3 | 1.639 | 41.6 |
2 1/4 | D 1/2 | 0.530 | 13.5 | 1.664 | 42.3 |
2 1/2 | E | 0.538 | 13.7 | 1.689 | 42.9 |
2 3/4 | E 1/2 | 0.546 | 13.9 | 1.714 | 43.5 |
3 | F | 0.554 | 14.1 | 1.740 | 44.2 |
3 1/4 | F 1/2 | 0.562 | 14.3 | 1.765 | 44.8 |
3 1/2 | G | 0.570 | 14.5 | 1.790 | 45.5 |
3 3/4 | G 1/2 | 0.578 | 14.7 | 1.815 | 46.1 |
4 | H | 0.586 | 14.9 | 1.840 | 46.7 |
4 1/4 | H 1/2 | 0.594 | 15.1 | 1.865 | 47.4 |
4 1/2 | I | 0.602 | 15.3 | 1.890 | 48.0 |
4 3/4 | J | 0.610 | 15.5 | 1.915 | 48.7 |
5 | J 1/2 | 0.618 | 15.7 | 1.941 | 49.3 |
5 1/4 | K | 0.626 | 15.9 | 1.966 | 49.9 |
5 1/2 | K 1/2 | 0.634 | 16.1 | 1.991 | 50.6 |
5 3/4 | L | 0.642 | 16.3 | 2.016 | 51.2 |
6 | L 1/2 | 0.650 | 16.5 | 2.041 | 51.8 |
6 1/4 | M | 0.658 | 16.7 | 2.066 | 52.5 |
6 1/2 | M 1/2 | 0.666 | 16.9 | 2.091 | 53.1 |
6 3/4 | N | 0.674 | 17.1 | 2.116 | 53.8 |
7 | N 1/2 | 0.682 | 17.3 | 2.141 | 54.4 |
7 1/4 | O | 0.690 | 17.5 | 2.167 | 55.0 |
7 1/2 | O 1/2 | 0.698 | 17.7 | 2.192 | 55.7 |
7 3/4 | P | 0.706 | 17.9 | 2.217 | 56.3 |
8 | P 1/2 | 0.714 | 18.1 | 2.242 | 56.9 |
8 1/4 | Q | 0.722 | 18.3 | 2.267 | 57.6 |
8 1/2 | Q 1/2 | 0.730 | 18.5 | 2.292 | 58.2 |
8 3/4 | R | 0.738 | 18.7 | 2.317 | 58.9 |
9 | R 1/2 | 0.746 | 18.9 | 2.342 | 59.5 |
9 1/4 | S | 0.754 | 19.2 | 2.368 | 60.1 |
9 1/2 | S 1/2 | 0.762 | 19.4 | 2.393 | 60.8 |
9 3/4 | T | 0.770 | 19.6 | 2.418 | 61.4 |
10 | T 1/2 | 0.778 | 19.8 | 2.443 | 62.1 |
10 1/4 | U | 0.786 | 20.0 | 2.468 | 62.7 |
10 1/2 | U 1/2 | 0.794 | 20.2 | 2.493 | 63.3 |
10 3/4 | V | 0.802 | 20.4 | 2.518 | 64.0 |
11 | V 1/2 | 0.810 | 20.6 | 2.543 | 64.6 |
11 1/4 | W | 0.818 | 20.8 | 2.569 | 65.2 |
11 1/2 | W 1/2 | 0.826 | 21.0 | 2.594 | 65.9 |
11 3/4 | X | 0.834 | 21.2 | 2.619 | 66.5 |
12 | X 1/2 | 0.842 | 21.4 | 2.644 | 67.2 |
12 1/4 | Y | 0.850 | 21.6 | 2.669 | 67.8 |
12 1/2 | Z | 0.858 | 21.8 | 2.694 | 68.4 |
12 3/4 | Z 1/2 | 0.866 | 22.0 | 2.719 | 69.1 |
13 | 0.874 | 22.2 | 2.744 | 69.7 | |
13 1/4 | Z1 | 0.882 | 22.4 | 2.769 | 70.3 |
13 1/2 | 0.890 | 22.6 | 2.795 | 71.0 | |
13 3/4 | Z2 | 0.898 | 22.8 | 2.820 | 71.6 |
14 | Z3 | 0.906 | 23.0 | 2.845 | 72.3 |
14 1/4 | 0.914 | 23.2 | 2.870 | 72.9 | |
14 1/2 | Z4 | 0.922 | 23.4 | 2.895 | 73.5 |
14 3/4 | 0.930 | 23.6 | 2.920 | 74.2 | |
15 | 0.938 | 23.8 | 2.945 | 74.8 | |
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 | |
16 | 0.970 | 24.6 | 3.046 | 77.4 | |
16 1/4 | 0.978 | 24.8 | 3.071 | 78.0 | |
16 1/2 | 0.986 | 25.0 | 3.096 | 78.6 | |
16 3/4 | 0.994 | 25.2 | 3.121 | 79.3 | |
17 | 1.002 | 25.5 | 3.146 | 79.9 | |
17 1/4 | 1.010 | 25.7 | 3.171 | 80.6 | |
17 1/2 | 1.018 | 25.9 | 3.197 | 81.2 | |
17 3/4 | 1.026 | 26.1 | 3.222 | 81.8 | |
18 | 1.034 | 26.3 | 3.247 | 82.5 | |
18 1/4 | 1.042 | 26.5 | 3.272 | 83.1 | |
18 1/2 | 1.050 | 26.7 | 3.297 | 83.7 | |
18 3/4 | 1.058 | 26.9 | 3.322 | 84.4 | |
19 | 1.066 | 27.1 | 3.347 | 85.0 | |
19 1/4 | 1.074 | 27.3 | 3.372 | 85.7 | |
19 1/2 | 1.082 | 27.5 | 3.397 | 86.3 | |
19 3/4 | 1.090 | 27.7 | 3.423 | 86.9 | |
20 | 1.098 | 27.9 | 3.448 | 87.6 | |
20 1/4 | 1.106 | 28.1 | 3.473 | 88.2 | |
20 1/2 | 1.114 | 28.3 | 3.498 | 88.8 | |
20 3/4 | 1.122 | 28.5 | 3.523 | 89.5 | |
21 | 1.130 | 28.7 | 3.548 | 90.1 | |
21 1/4 | 1.138 | 28.9 | 3.573 | 90.8 | |
21 1/2 | 1.146 | 29.1 | 3.598 | 91.4 | |
21 3/4 | 1.154 | 29.3 | 3.624 | 92.0 | |
22 | 1.162 | 29.5 | 3.649 | 92.7 | |
22 1/4 | 1.170 | 29.7 | 3.674 | 93.3 | |
22 1/2 | 1.178 | 29.9 | 3.699 | 94.0 | |
22 3/4 | 1.186 | 30.1 | 3.724 | 94.6 | |
23 | 1.194 | 30.3 | 3.749 | 95.2 | |
23 1/4 | 1.202 | 30.5 | 3.774 | 95.9 | |
23 1/2 | 1.210 | 30.7 | 3.799 | 96.5 | |
23 3/4 | 1.218 | 30.9 | 3.825 | 97.1 | |
24 | 1.226 | 31.1 | 3.850 | 97.8 | |
24 1/4 | 1.234 | 31.3 | 3.875 | 98.4 | |
24 1/2 | 1.242 | 31.5 | 3.900 | 99.1 | |
24 3/4 | 1.250 | 31.8 | 3.925 | 99.7 | |
25 | 1.258 | 32.0 | 3.950 | 100.3 | |
25 1/4 | 1.266 | 32.2 | 3.975 | 101.0 | |
25 1/2 | 1.274 | 32.4 | 4.000 | 101.6 | |
25 3/4 | 1.282 | 32.6 | 4.025 | 102.2 | |
26 | 1.290 | 32.8 | 4.051 | 102.9 |