Ring Sizes Around US 7
| US | UK | ISO / EU | JP / KR | Diameter (mm) | Circumference (mm) |
| 5.5 | K | 51 | 10 | 16.1 | 50.6 |
| 6 | L | 52 | 12 | 16.5 | 51.9 |
| 6.5 | M | 53 | 13 | 16.9 | 53.1 |
| 7 | N | 54 | 14 | 17.3 | 54.4 |
| 7.5 | O | 56 | 15 | 17.7 | 55.7 |
| 8 | P | 57 | 16 | 18.1 | 57 |
| 8.5 | Q | 58 | 18 | 18.6 | 58.3 |
Frequently Asked Questions
Does US 7 round up or down in ISO?
Round to clear the knuckle; a size 7 that grips the base but sticks at the joint is the classic reason rings get stuck, so favour the looser fit.
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