Ring size 8.5 in millimetres

US ring size 8.5 is 18.54 mm inner diameter and 58.3 mm circumference.

Proportional only — actual on-screen size depends on your display.

50 mm reference

Actual-size print check Inner diameter: 18.54 mm. Print at 100% and verify the 50 mm reference bar before comparing a ring.

This sits between the average women’s (US 6–6½) and men’s (US 9–10) sizes. See the full international ring size chart · Converter

Frequently asked questions

What is ring size 8.5 in mm?

US ring size 8.5 has an inner diameter of 18.54 mm and an inner circumference of 58.3 mm.

What is US 8.5 in UK, EU and Japan ring sizes?

US 8.5 converts to UK Q½, EU/ISO 58, Japan 17, and Switzerland/Italy/Spain 18.

Is ring size 8.5 small or large?

This sits between the average women’s (US 6–6½) and men’s (US 9–10) sizes.