convertimate Ring size

Diameter (mm) to US sizes

Type a value in ⌀ mm to get it in US instantly.

6.976US

That's 1.05× as big as an average women’s ring, while an average men’s ring is 1.1× bigger. That is about 17.3 mm across the inside.

What it means

How big is that ring?

Measure a ring that fits across its inside, or wrap a strip of paper around the finger. Fingers swell in heat, so measure warm.

The math

How to convert ⌀ mm to US

Each scale steps differently: EU = circumference in mm, US = (circumference − 36.54) ÷ 2.55, and the diameter is the circumference divided by π.

Example: 17.3 ⌀ mm = 6.97574 US.

Every unit

Your ring size in every system

Tables

⌀ mm to US conversion table

⌀ mm to US conversion table
⌀ mmUS
14.1 ⌀ mm3.03875 US
14.9 ⌀ mm4.023 US
15.7 ⌀ mm5.00725 US
16.5 ⌀ mm5.99149 US
17.3 ⌀ mm6.97574 US
18.1 ⌀ mm7.95999 US
18.9 ⌀ mm8.94423 US
19.8 ⌀ mm10.0515 US
20.6 ⌀ mm11.0358 US
21.4 ⌀ mm12.02 US
22.2 ⌀ mm13.0043 US
US to ⌀ mm conversion table
US to ⌀ mm conversion table
US⌀ mm
3 US14.0685 ⌀ mm
4 US14.8813 ⌀ mm
5 US15.6941 ⌀ mm
6 US16.5069 ⌀ mm
7 US17.3197 ⌀ mm
8 US18.1325 ⌀ mm
9 US18.9453 ⌀ mm
10 US19.7581 ⌀ mm
11 US20.5709 ⌀ mm
12 US21.3837 ⌀ mm
13 US22.1965 ⌀ mm

Quick answers

Quick answers

How many US is 17.3 ⌀ mm?
17.3 ⌀ mm is 6.97574 US.

The units

About these units

Diameter (mm) (⌀ mm)

The inside distance across the ring. Circumference divided by π.

US sizes (US)

American numeric sizes, stepping 2.55 mm of circumference each whole size.

Learn more about ring size units

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