Size Studio
UK Ring Size U in US, EU and mm
A UK (and Australian) ring size U is about a US 10.25 and an EU 63, with an inside diameter of about 19.9 mm (62.5 mm around).
| US / CA | UK / AU | EU (ISO) | Japan | Inside diameter | Inside circumference |
|---|---|---|---|---|---|
| 10.25 | U | 63 | 22 | 19.9 mm | 62.5 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: TLarger: VOpen the full converterHow to measure yourself
Questions
What is ring size U in mm?
About 19.9 mm inside diameter, 62.5 mm around.
What is UK ring size U in US?
About US 10.25.
What is ring size U in EU?
EU 63.
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