International Ring Size Conversion: Ring Size Chart & Guide

It can be tricky to figure out ring sizing from another country. For instance, a ring could be a US 7, UK N, EU 54, or 54.5 mm circumference, even though these may refer to the same size.

For quick reference, this guide covers international ring size conversions. If you know your ring size, the chart below can help you find the closest equivalent in a different sizing system. 

Don't know your ring size yet? Read Taniah Jewellery's Find Your Ring Size guide first. This article focuses on conversion and comparison, rather than measuring your finger.

International Ring Size Conversion Chart

The most helpful way to compare international ring sizes is by US/Canada size, UK/Australia letter size, European size, inside diameter, and inside circumference.

International conversions can vary slightly by sizing standard and retailer. Use the chart as a reference and confirm sizing with the jeweller before ordering a ring. GIA and GS Diamonds both publish international ring-size charts, but their tables use slightly different increments and regional groupings.

What Do the Different Ring-Size Systems Mean?

No single ring-size system is used worldwide.

US & Canada

Ring sizes are generally expressed using numbers, such as:

6, 7, 8, 9 or 10

Quarter and half sizes may also be available.

UK & Australia

Ring sizes commonly use letters, including half sizes:

L, L½, M, M½, N, N½, and so on.

European sizing

The European approach to ring sizes assigns a number that relates almost directly to the ring's total circumference in millimeters.

 For example, a ring with an internal circumference of about 54 mm is a European size 54.

Ring Size in Millimetres

When aligning different international sizing systems, it helps to use a consistent unit of measure, such as millimeters.

Inside diameter

Measure the inside diameter by going across the ring straight through the center.

Inside circumference

Measure the inside circumference by going around the ring.

For example, converting inside measurements for a ring about 17.3 mm in diameter with an inside circumference of approximately 54.4–54.5 mm can vary based on the conversion table used.

Millimeter measurements can be especially helpful when buying a ring internationally.

Quick Ring Size Conversions

If you already know your size, here are a few commonly searched examples.

US 6 → approximately UK L½ → EU 52

US 7 → approximately UK N½ → EU 54–54.5

US 8 → approximately UK P½ → EU 57

US 9 → approximately UK R½ → EU 59.5

US 10 → approximately UK T½ → EU 62 

These examples are good reference points, but individual size conversion charts may vary slightly because different international size systems don't use the same increments.

Buying a Ring From Another Country?

International conversion comes in handy when:

• Buying Jewellery from an overseas retailer
• Ordering a ring as a gift
• Comparing rings listed in different sizing systems
• Travelling and shopping internationally
• Using an existing ring size from another country
• Ordering a custom ring

For example, if your normal size is a US 7, a retailer using UK sizing may require a letter size instead.

Don’t guess. Use the conversion chart to determine your size, then confirm with the retailer.

What If You're Between Two Sizes?

A conversion chart gives you a reference, but can't account for the many factors that affect how a ring feels. 

Width matters. A wider band can feel more snug than a narrow band in the same size. Brilliant Earth notes that wider rings may require a different size.

Your finger shape, knuckle size, and the ring design can also affect the fit.

If your measurement is between sizes, don’t base your decision on the number.

For a more accurate sizing, see Taniah Jewellery’s Find Your Ring Size guide.

Ring Sizes Are Not “Men's” or “Women's” Sizes

Ring-size systems are not gendered.

A US 7, UK N, or EU 54 are the same measurements, regardless of the wearer.

What differs is the style or band width people choose.

This shows that international conversion standards for all other Rings, from Engagement Rings and Wedding Rings, to all other Men’s and Women’s Rings, and jewellery, can be applied as well.

A Note About Ring Size Conversion

A conversion chart is just that, a chart for conversion. Don't treat it as an absolute.

Different jewellery stores and workshops, and even different regions, may show slightly different numbers, especially in half and quarter sizes. GIA's international chart and GS Diamonds’ conversion chart show some of these differences.

For a custom piece of jewellery, as an example, a custom ring, always confirm the size with the jeweller before they make it or place the order.

Need to Find Your Ring Size First?

Don't convert your size using the charts. 

Don't guess your size. Instead, begin with Taniah Jewellery's ‘Find Your Ring Size’ guide to determine your size with a simple measurement of your finger or an existing ring.

Once you learn your size, you will know it in all international sizing systems when you use this chart again.

Explore More From Taniah Jewellery

Planning an engagement ring?

Read the Engagement Ring Guide.

Choosing a wedding band?

Explore the Wedding Ring Guide.

Exploring different designs?

Read our Design Basics and our Engagement Ring Styles and Setting Types.

Creating something personalised?

Check out Taniah Jewellery's Custom Ring Journey and Our Process.

Getting your size may seem like a small detail, but it gives each customer the satisfaction that their jewellery is perfect, and they can enjoy wearing it.