| Diameter (mm) | Circumference (mm) | US | Europe | Swiss |
| 14.10 | 44.20 | 3 | 44 | 4 |
| 14.90 | 46.80 | 4 | 47 | 7 |
| 15.70 | 49.30 | 5 | 50 | 10 |
| 16.90 | 53.10 | 6 | 53 | 13 |
| 17.50 | 55.10 | 7 | 55 | 15 |
| 18.10 | 57.00 | 8 | 57 | 18 |
| 19.00 | 59.50 | 9 | 59 | 20 |
| 19.80 | 62.10 | 10 | 62 | 22 |
| 21.00 | 65.90 | 11 | 65 | 25 |
| 21.40 | 67.20 | 12 | 67 | 27 |
Our favorite way to find out a ring size is to take a piece of string, wrap it around the base of the finger and cut at the correct size. Using a millimetre ruler, then measure the length of the string. Use the above chart and check which circumference matches yours!