Reference Tool
Ring Size Converter
Tap any row to highlight and convert across all sizing systems
| US / Canada | UK / AU | EU | Japan | Diameter (mm) | Circumference (mm) |
|---|---|---|---|---|---|
| 3 | F | 44 | 4 | 14.1 | 44.2 |
| 3.5 | G | 45 | 6 | 14.5 | 45.5 |
| 4 | H | 47 | 7 | 14.9 | 46.8 |
| 4.5 | I | 48 | 8 | 15.3 | 48 |
| 5 | J | 49 | 9 | 15.7 | 49.3 |
| 5.5 | K | 51 | 11 | 16.1 | 50.6 |
| 6 | L | 52 | 12 | 16.5 | 51.9 |
| 6.5 | M | 54 | 14 | 16.9 | 53.1 |
| 7 | N | 55 | 15 | 17.3 | 54.4 |
| 7.5 | O | 57 | 16 | 17.7 | 55.7 |
| 8 | P | 58 | 18 | 18.1 | 56.9 |
| 8.5 | Q | 59 | 19 | 18.5 | 58.2 |
| 9 | R | 61 | 20 | 18.9 | 59.5 |
| 9.5 | S | 62 | 22 | 19.4 | 60.8 |
| 10 | T | 63 | 23 | 19.8 | 62.1 |
| 10.5 | U | 65 | 25 | 20.2 | 63.4 |
| 11 | V | 66 | 26 | 20.6 | 64.6 |
| 11.5 | W | 68 | 27 | 21 | 65.9 |
| 12 | X | 69 | 29 | 21.4 | 67.2 |
| 12.5 | Y | 71 | 30 | 21.8 | 68.5 |
| 13 | Z | 72 | 31 | 22.2 | 69.7 |
Size conversions are approximate. For high-value jewelry, always confirm sizing with a professional before purchase.