Size Studio
Ring Size 9 in UK, EU and Inside Diameter (mm)
A US (and Canadian) ring size 9 is a UK R½ and an EU 59, with an inside diameter of about 18.9 mm (59.5 mm around).
| US / CA | UK / AU | EU (ISO) | Japan | Inside diameter | Inside circumference |
|---|---|---|---|---|---|
| 9 | R½ | 59 | 19 | 18.9 mm | 59.5 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: 8.5Larger: 9.5Open the full converterHow to measure yourself
Questions
What is ring size 9 in mm?
About 18.9 mm inside diameter, 59.5 mm around.
What is ring size 9 in UK?
UK R½.
What is ring size 9 in EU?
EU 59.
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