Ring Sizes Around ISO 56
| US | UK | ISO / EU | JP / KR | Diameter (mm) | Circumference (mm) |
| 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 |
| 9 | R | 60 | 19 | 18.9 | 59.5 |
Frequently Asked Questions
Does ISO 56 round up or down in UK?
Fingers swell through the day, so size a 7.5 to fit in the evening when the hand is largest; a morning-perfect ring can bind by nightfall.
See a number that looks off? Report an error on this page.