Size Studio
Ring Size 12 in UK, EU and Inside Diameter (mm)
A US (and Canadian) ring size 12 is a UK X½ and an EU 67, with an inside diameter of about 21.4 mm (67.1 mm around).
| US / CA | UK / AU | EU (ISO) | Japan | Inside diameter | Inside circumference |
|---|---|---|---|---|---|
| 12 | X½ | 67 | 26 | 21.4 mm | 67.1 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: 11.5Larger: 12.5Open the full converterHow to measure yourself
Questions
What is ring size 12 in mm?
About 21.4 mm inside diameter, 67.1 mm around.
What is ring size 12 in UK?
UK X½.
What is ring size 12 in EU?
EU 67.
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