US 4.5 to EU ring size

US ring size 4.5 is EU 48 — 15.29 mm inner diameter (48.0 mm circumference).

Your size is US 4.5 (UK I½, EU 48).

Fit confidence Exact table match

Measurement confidence 70/100 · Medium Standard chart conversion; final fit still depends on band width and knuckle shape. Confirm with a printable or physical sizer before ordering an expensive ring.

US
4.5
UK
EU / ISO
48
Japan
8
CH / IT / ES
8
Ø mm
15.29
Circ mm
48.0

Open US 4.5 size guide

Print Smart rings Wallet Physical sizer Local only; no account.

Nearby sizes

USEUØ mm
44714.88
54915.70

Frequently asked questions

What is US 4.5 in EU ring size?

US ring size 4.5 is EU 48 (inner diameter 15.29 mm, circumference 48.0 mm).

Is US 4.5 the same as EU 48?

Yes — a US size 4.5 ring equals EU 48. They are different scales for the same physical size (15.29 mm inner diameter).

Explore

Ring Size Conversions — All Systems & Sizes · Size 4.5 · See the full international ring size chart