Size Studio
UK Ring Size J in US, EU and mm
A UK (and Australian) ring size J is about a US 4.75 and an EU 49, with an inside diameter of about 15.5 mm (48.8 mm around).
| US / CA | UK / AU | EU (ISO) | Japan | Inside diameter | Inside circumference |
|---|---|---|---|---|---|
| 4.75 | J | 49 | 9 | 15.5 mm | 48.8 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: ILarger: KOpen the full converterHow to measure yourself
Questions
What is ring size J in mm?
About 15.5 mm inside diameter, 48.8 mm around.
What is UK ring size J in US?
About US 4.75.
What is ring size J in EU?
EU 49.
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