Size Studio
UK Ring Size R in US, EU and mm
A UK (and Australian) ring size R is about a US 8.75 and an EU 59, with an inside diameter of about 18.7 mm (58.8 mm around).
| US / CA | UK / AU | EU (ISO) | Japan | Inside diameter | Inside circumference |
|---|---|---|---|---|---|
| 8.75 | R | 59 | 18 | 18.7 mm | 58.8 mm |
Good to know
- EU (ISO) ring sizes are the inside circumference in millimetres. US sizes go up about 0.8 mm in diameter per whole size, UK letters about 0.4 mm.
- Fingers swell when warm. Measure at the end of the day, and go half a size up for wide bands.
Sizes either side
Smaller: QLarger: SOpen the full converterHow to measure yourself
Questions
What is ring size R in mm?
About 18.7 mm inside diameter, 58.8 mm around.
What is UK ring size R in US?
About US 8.75.
What is ring size R in EU?
EU 59.
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