Size Studio
Ring Size 4.5 in UK, EU and Inside Diameter (mm)
A US (and Canadian) ring size 4.5 is a UK I½ and an EU 48, with an inside diameter of about 15.3 mm (48 mm around).
| US / CA | UK / AU | EU (ISO) | Japan | Inside diameter | Inside circumference |
|---|---|---|---|---|---|
| 4.5 | I½ | 48 | 8 | 15.3 mm | 48 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: 4Larger: 5Open the full converterHow to measure yourself
Questions
What is ring size 4.5 in mm?
About 15.3 mm inside diameter, 48 mm around.
What is ring size 4.5 in UK?
UK I½.
What is ring size 4.5 in EU?
EU 48.
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