convertimate Ring size

Japanese sizes to US sizes

Type a value in JP to get it in US instantly.

4.098US

That's 1.07× as big as a child’s ring, while an average women’s ring is 1.11× bigger. That is about 14.96 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 JP 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: 7 JP = 4.09751 US.

Every unit

Your ring size in every system

Tables

JP to US conversion table

JP to US conversion table
JPUS
3 JP2.53104 US
4 JP2.92266 US
5 JP3.31427 US
6 JP3.70589 US
7 JP4.09751 US
8 JP4.48913 US
9 JP4.88075 US
10 JP5.27237 US
11 JP5.66399 US
12 JP6.05561 US
13 JP6.44723 US
US to JP conversion table
US to JP conversion table
USJP
3 US4.1975 JP
4 US6.751 JP
5 US9.3045 JP
6 US11.858 JP
7 US14.4115 JP
8 US16.965 JP
9 US19.5185 JP
10 US22.072 JP
11 US24.6255 JP
12 US27.179 JP
13 US29.7325 JP

Quick answers

Quick answers

How many US is 1 JP?
1 JP is 1.7478 US.
How many US is 10 JP?
10 JP is 5.27237 US.
How many US is 7 JP?
7 JP is 4.09751 US.

The units

About these units

Japanese sizes (JP)

Japanese sizes: size 1 is 41 mm round, and each size adds 1 mm.

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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