Size Studio
UK Ring Size K in US, EU and mm
A UK (and Australian) ring size K is about a US 5.25 and an EU 50, with an inside diameter of about 15.9 mm (50 mm around).
| US / CA | UK / AU | EU (ISO) | Japan | Inside diameter | Inside circumference |
|---|---|---|---|---|---|
| 5.25 | K | 50 | 10 | 15.9 mm | 50 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: JLarger: LOpen the full converterHow to measure yourself
Questions
What is ring size K in mm?
About 15.9 mm inside diameter, 50 mm around.
What is UK ring size K in US?
About US 5.25.
What is ring size K in EU?
EU 50.
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