Ring Size Converter (US, UK, mm)
Convert ring sizes between US, UK and millimeter diameter and circumference.
| US | UK | Diameter (mm) | Circumference (mm) |
|---|---|---|---|
| 5 | J½ | 15.7 | 49.3 |
| 6 | L½ | 16.5 | 51.9 |
| 7 | N½ | 17.3 | 54.4 |
| 8 | P½ | 18.1 | 57 |
| 9 | R½ | 18.9 | 59.5 |
| 10 | T½ | 19.8 | 62.1 |
| 11 | V½ | 20.6 | 64.6 |
| 12 | X½ | 21.4 | 67.2 |
| 13 | Z+1 | 22.2 | 69.7 |
Measure the inside diameter of a ring that fits, then match the closest row.
About this tool
Convert ring sizes between US, UK and millimeter diameter and circumference.
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