What ring size is 18 mm?
A 18 mm inner diameter is a US 8 — UK P½, EU 57, Japan 16. (between sizes — we suggest sizing up)
- US
- 8
- UK
- P½
- EU
- 57
- Japan
- 16
- Ø mm
- 18
- Circ mm
- 56.5
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Frequently asked questions
What ring size is 18 mm?
A 18 mm inner diameter is closest to US 8 (UK P½, EU 57, Japan 16). It falls between sizes, so we suggest sizing up.
Is 18 mm a diameter or circumference?
On this page 18 mm is the inner diameter (the width across the inside of the ring). The matching inner circumference is about 56.5 mm.