Rings Size Guide
| Sizes | Inside Diameter | Inside Circumference | |
|---|---|---|---|
| US & Canada | British & Australian | MM | MM |
| 4 | H 1/2 | 14.86 | 46.68 |
| 4 1/4 | I | 15.04 | 47.25 |
| 4 1/2 | I 1/2 | 25.27 | 47.97 |
| 4 3/4 | J 1/4 | 15.53 | 48.79 |
| 5 | J 1/2 | 15.7 | 49.32 |
| 5 1/4 | K 1/4 | 15.9 | 49.95 |
| 5 1/2 | L | 16.1 | 50.58 |
| 5 3/4 | L 1/4 | 16.3 | 51.21 |
| 6 | M | 16.51 | 51.87 |
| 6 1/4 | M 1/2 | 16.71 | 52.5 |
| 6 1/2 | N | 16.92 | 53.16 |
| 6 3/4 | N 1/2 | 17.13 | 53.82 |
| 7 | O | 17.35 | 54.51 |
| 7 1/4 | O 1/2 | 17.45 | 54.82 |
| 7 1/2 | P | 17.75 | 55.76 |
| 7 3/4 | P 1/2 | 17.97 | 56.45 |
| 8 | Q | 18.19 | 57.15 |
| 8 1/4 | Q 1/2 | 18.35 | 57.65 |
| 8 1/2 | Q 3/4 | 18.53 | 58.21 |
| 8 3/4 | R 1/4 | 18.69 | 58.72 |
| 9 | R 3/4 | 18.89 | 59.34 |



