Size Studio
Ring Size 8 in UK, EU and Inside Diameter (mm)
A US (and Canadian) ring size 8 is a UK P½ and an EU 57, with an inside diameter of about 18.1 mm (56.9 mm around).
| US / CA | UK / AU | EU (ISO) | Japan | Inside diameter | Inside circumference |
|---|---|---|---|---|---|
| 8 | P½ | 57 | 16 | 18.1 mm | 56.9 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: 7.5Larger: 8.5Open the full converterHow to measure yourself
Questions
What is ring size 8 in mm?
About 18.1 mm inside diameter, 56.9 mm around.
What is ring size 8 in UK?
UK P½.
What is ring size 8 in EU?
EU 57.
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