International Ring Size Conversion Tool + Chart

Ring sizes can be confusing, which is why I created a free conversion tool above that lets you quickly and easily see what the equivalent UK, US, European, Swiss, Japanese, Indian and Brazilian ring sizes are.

Select Ring Size:

UKUSAEuropeSwitzerlandJapanIndiaBrazilDiameterCircumference

mminches

mm in

UK:
N/A

D: N/A
C: N/A

Closest Match

US:
N/A

D: N/A
C: N/A

Closest Match

Europe:
N/A

D: N/A
C: N/A

Closest Match

Switzerland:
N/A

D: N/A
C: N/A

Closest Match

Japan:
N/A

D: N/A
C: N/A

Closest Match

India:
N/A

D: N/A
C: N/A

Closest Match

Brazil:
N/A

D: N/A
C: N/A

Closest Match

D = diameter, C = circumference

I have tried to make this tool and the charts as accurate as possible but some countries don’t have an official size list (or at least one that I could find), so I used multiple resources for the sizes used in the tool.

One of the things that is confusing about ring sizes is which country uses which chart, so below, I have listed which countries use which chart:

UK Ring Sizes – uses the Wheatsheaf™ size chart, a lettered chart that ranges from A-Z and also uses half sizes and larger Z+ sizes.

Also Used By – Ireland, Australia, New Zealand and South Africa

US Ring Sizes – a numbered chart that usually starts at 1 and increases in 1/4 increments.

Also Used By – Canada and Mexico

EU Ring Sizes – follows the ISO 8563 standard with the size being determined by the inner circumference of the ring.

Used By – France, Austria, Belgium, Norway, Sweden, Finland and Denmark

Swiss Ring Sizes – follows the ISO 8563 standard but uses the Inner Circumference – 40 for its numbering.

Also Used By – Spain, Italy and the Netherlands

Japanese Ring Sizes – while Japan has officially adopted the JIS S 4700:2022 standard, which aligns with the ISO 8563, most Japanese jewellers still use the JCS (Japan Custom Size) standard, which is what I have used.

Indian Ring Sizes – a numbered chart that ranges from 1 – 30.

Brazilian Ring Sizes – Brazil uses the ABNT NBR 16058:2012 standard, which closely aligns with the ISO 8653 standard.

How To Measure Your Ring Size

1. Get it measured – I always recommend getting your ring size measured by a professional as this removes any guesswork
2. Use a ring sizer – you can buy these on Amazon (UK and US)
3. Downloadable ring sizer – these are ring sizers you can print and then cut out to check (you can download my UK and US versions below)
• UK Ring Size Tool
• US Ring Size Tool

I’ve also got a couple of tips for measuring your ring size:

• Measure your ring size when your hands are at a normal temperature – measuring when your hands are hot or cold can give you an incorrect measurement
• Measure multiple times – ideally measure in the morning, at midday and in the evening as your fingers do fluctuate in size throughout the day

Ring Size Charts