Size Studio
Ring Size 10.5 in UK, EU and Inside Diameter (mm)
A US (and Canadian) ring size 10.5 is a UK U½ and an EU 63, with an inside diameter of about 20.1 mm (63.3 mm around).
| US / CA | UK / AU | EU (ISO) | Japan | Inside diameter | Inside circumference |
|---|---|---|---|---|---|
| 10.5 | U½ | 63 | 22 | 20.1 mm | 63.3 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: 10Larger: 11Open the full converterHow to measure yourself
Questions
What is ring size 10.5 in mm?
About 20.1 mm inside diameter, 63.3 mm around.
What is ring size 10.5 in UK?
UK U½.
What is ring size 10.5 in EU?
EU 63.
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