Ring Size Chart for All Countries 2026 – Complete International Guide

Ring Size Chart for All Countries 2026

The complete international ring size chart — UK, US/Canada, EU, France/Switzerland/Italy/Spain, Japan/China/Korea, India, Brazil, Russia and more. Full conversion table, world map, smart calculator and country-by-country guide.

🇬🇧 UK · A–Z+9 🇺🇸 US · 0–17 🇪🇺 EU/ISO · 37–80 🇫🇷 French · 1–40 🇯🇵 Japan · 1–40 🇮🇳 India · 1–40 🇧🇷 Brazil · 1–40 📅 Updated 2026

🗺️ International Ring Size Systems — World Map

Which Ring Size System Does Each Country Use?

7 major ring sizing systems are used worldwide. Colour-coded by region — click the legend to learn each system.

🇬🇧

British / UK System

Used in UK, Ireland, Australia, NZ and many Commonwealth nations. Letter-based: A–Z+9.

🇬🇧 🇮🇪 🇦🇺 🇳🇿 🇿🇦 🇮🇳*

UK Size M = 15.9mm

🇺🇸

US / Canada System

Used in USA, Canada and Mexico. Number-based in 0.032" increments. Half sizes common.

🇺🇸 🇨🇦 🇲🇽

US Size 6 = UK M

🇩🇪

EU / ISO System

Used in Germany, Netherlands, Sweden, Russia, Poland. Size = inner circumference in mm.

🇩🇪 🇷🇺 🇸🇪 🇳🇱 🇵🇱

EU 50 = 50mm circ.

🇫🇷

French System

Also called Swiss/Italian/Spanish system. Size = circumference(mm) − 40. Same formula all four countries.

🇫🇷 🇨🇭 🇮🇹 🇪🇸 🇧🇪

FR 10 = 50mm circ.

🇯🇵

Japanese System

JIS S 4700:2022. Based on inner diameter in 0.33mm steps from 13mm. Used in Japan, China, Korea.

🇯🇵 🇨🇳 🇰🇷 🇸🇬 🇹🇼

JP 13 = US 6

🇮🇳

Indian System

Used in India. Diameter-based in ~0.3–0.4mm increments from 13mm. Range 1–40. No ISO standard.

🇮🇳

India 13 = US 6

🇧🇷

Brazil System

NBR 16058. T = (D×π)−40 where D = inner diameter mm. Closely mirrors Japanese and French systems.

🇧🇷 🇵🇪 🇧🇴

Brazil 10 = EU 50

🌍 Major Ring Size
Systems Worldwide

100+

🗺️ Countries Covered
in This Chart

ISO

📐 International Standard
ISO 8653:2016

📏 Universal Reference
Inner Diameter (mm)

ℹ️

Ring Size Chart for All Countries — 2026 Guide

There are 7 major ring sizing systems used worldwide, governed by international standards including ISO 8653:2016 (EU/Germany/Russia), JIS S 4700:2022 (Japan/China/Korea), BS EN 28653:1993 (UK/Australia) and NBR 16058 (Brazil). The universal reference is inner diameter in millimetres — measure this once and convert to any country's system instantly. The UK uses letters (A–Z+9), the US uses numbers (0–17), the EU uses the raw circumference in mm, France/Switzerland/Italy/Spain use circumference minus 40, while Japan, India, and Brazil all use number systems based on inner diameter.

🧮 International Ring Size Calculator — All Countries

Enter any measurement to instantly convert to all international ring size systems

Your Ring Size — All Countries

📊 Ring Size Chart — All Countries 2026 (Full Conversion Table)

📏 Scroll right on mobile →

💗 Women's avg highlighted

💙 Men's avg highlighted

🔒 Sticky diameter column

📐 Diam. mm	⭕ Circ. mm	🇬🇧 UK Ire/Aus/NZ	🇺🇸 US CA/MX	🇩🇪 EU ISO/Russia	🇫🇷 French CH/IT/ES	🇯🇵 Japan CN/KR	🇮🇳 India	🇧🇷 Brazil	👩👨 Type

Sources: ISO 8653:2016 · JIS S 4700:2022 · BS EN 28653:1993 · NBR 16058

French size = EU size − 40

Russia uses EU/ISO mm circumference directly

📐 How Each Country Calculates Ring Size — Formulas

🇬🇧 UK / British (ISO 8653)

Letter A to Z+9

Based on inner circumference. Size A = 37.5mm. Each full letter = ~1.25mm increment. Updated by BS EN 28653:1993.

🇺🇸 US / Canada

Size = (D × π − 36.5) ÷ 0.8128

Based on inner diameter in inches. Each size = 0.032 inches. Half sizes common. Range 0–17. No ISO standard.

🇩🇪 EU / ISO / Russia (ISO 8653:2016)

Size = Circumference (mm)

The simplest system. Ring size equals inner circumference in mm. Range 41–76. 1mm per size. Russia uses this directly.

🇫🇷 French / Swiss / Italian / Spanish

Size = Circumference (mm) − 40

Based on ISO circumference minus 40. EU size 50 = French size 10. All four countries use the identical formula.

🇯🇵 Japan / China / Korea (JIS S 4700:2022)

Size 1 = 13mm diameter

Each size adds 0.33mm to inner diameter. Size 13 = 17mm. Used in Japan, China, South Korea, Singapore, Taiwan.

🇮🇳 India

Size 1 = ~13mm · ~0.35mm/size

Non-linear diameter-based system. Range 1–40. No official ISO standard. Closest to Japanese system but with slight offsets.

🇧🇷 Brazil (NBR 16058)

Size = (D × π) − 40

Where D = inner diameter in mm. Official formula matches ISO circumference minus 40. Practically identical to French system.

🗺️ Country-by-Country Ring Size System Directory

🇬🇧

United Kingdom

UK British System
Letters A–Z+9 · ISO BS EN 28653:1993

🇮🇪

Ireland

UK British System
Same as UK · Letters A–Z

🇦🇺

Australia

UK British System
Same letters as UK · A–Z+9

🇳🇿

New Zealand

UK British System
Same letters as UK · A–Z+9

🇺🇸

United States

US System
Numbers 0–17 · Half sizes

🇨🇦

Canada

US System
Same as US · 0–17

🇲🇽

Mexico

US System
Follows US sizing

🇩🇪

Germany

EU / ISO System
Circumference mm · 41–76

🇷🇺

Russia

EU / ISO System
Circumference mm · GOST 18288-88

🇳🇱

Netherlands

EU / ISO System
Circumference mm · 41–76

🇸🇪

Sweden

EU / ISO System
Circumference mm

🇵🇱

Poland

EU / ISO System
Circumference mm

🇫🇷

France

French System
Circ. − 40 · Range 1–40

🇨🇭

Switzerland

Swiss/French System
Circ. − 40 · Same formula

🇮🇹

Italy

Italian/French System
Circ. − 40 · Same formula

🇪🇸

Spain

Spanish/French System
Circ. − 40 · Same formula

🇧🇪

Belgium

French System
Circ. − 40 · Same formula

🇵🇹

Portugal

French/EU System
Follows French system

🇯🇵

Japan

Japanese System
JIS S 4700:2022 · 1–40

🇨🇳

China

Japanese-based System
Similar JIS numbering 1–33

🇰🇷

South Korea

Japanese System
JIS-based · 1–35

🇸🇬

Singapore

Japanese System
JIS-referenced sizing

🇹🇼

Taiwan

Japanese System
JIS-based numbering

🇮🇳

India

Indian System
Diameter-based · 1–40

🇧🇷

Brazil

Brazil System (NBR 16058)
(D×π)−40 · 1–40

🇦🇷

Argentina

Brazil/French-like
Circ. − 40 system

🇿🇦

South Africa

UK British System
Letters A–Z · Commonwealth

🇺🇦

Ukraine

EU / ISO System
Circumference mm (Russian standard)

💡 International Ring Sizing — Expert Tips

📏 Always convert via inner diameter in mm: When ordering rings from international websites — particularly Chinese marketplaces or US jewellers when you know your UK size — always convert via the inner diameter in millimetres. A UK Size M = 15.9mm diameter = US 6 = EU 50 = French 10 = Japan 13. Diameter mm is the one universal reference that never causes confusion between country systems.
🇩🇪🇫🇷 EU vs French size — don't confuse them: EU (Germany/Russia) ring size 50 and French size 50 mean completely different things. EU size 50 = 50mm circumference (a UK Size K, average women's size). French size 50 = 90mm circumference (an enormous size). Always confirm which system the seller is using before ordering from European websites.
🇨🇳 Ordering from Chinese websites: Chinese platforms (AliExpress, Shein, Temu) typically use the Japanese/Chinese numbering system (1–33), where size 13 ≈ US 6 ≈ UK M. However, some Chinese sellers use EU sizing or even provide diameter in mm directly. Always check the size chart on the specific product listing and compare the diameter mm to your known measurement before ordering.
🔄 Between-system rounding: Because each system uses different increment sizes (0.33mm for Japan, ~1.25mm for UK letters, 1mm for EU), conversions will not always be exact whole numbers. If your calculated conversion falls between two sizes in another country's system, always round up to the larger size — a marginally loose ring is far easier to wear than one that is too tight.
🛒 Buying from international jewellers online: Reputable international jewellers (including Tiffany, Cartier, Pandora) list sizes using both their regional system and a diameter mm/circumference mm reference. If only one unit is shown, use the calculator above to identify your size. When no reference is provided and you cannot confirm the sizing system, contact the retailer directly before placing the order.

❓ Ring Size Chart All Countries — FAQs

What is the most universal way to express ring size for all countries?▼

The most universally understood ring size reference is inner diameter in millimetres. Every country's sizing system can be derived from this single measurement. EU size equals inner circumference directly (diameter × π). French/Swiss/Italian/Spanish size equals circumference minus 40. UK size can be looked up by circumference. Japanese and Indian sizes start from 13mm diameter at size 1. Always ask for or state the inner diameter in mm when communicating ring sizes internationally.

Are the French, Swiss, Italian and Spanish ring size systems identical?▼

Yes — all four countries use the exact same formula: ring size = inner circumference in mm minus 40. A ring with a 54mm inner circumference is called size 14 in France, Switzerland, Italy, and Spain. They are sometimes referred to as different systems (Swiss system, Italian system) but the mathematics are identical. Since ISO 8653:2016, these countries officially use the EU/ISO circumference-based system, but the "minus 40" method remains widely practised in local jewellery trade.

Is Russia's ring size system the same as the EU system?▼

Effectively yes. Russia's ring sizing standard (GOST 18288-88) uses inner circumference in millimetres as the ring size, which is identical in practice to the ISO EU system. A Russian size 17 ring has a 17mm inner diameter and a circumference of approximately 53.4mm — equivalent to EU size 53, UK Size N, and US Size 7. Russian ring sizes may also be expressed as diameter in mm at some jewellers.

How do I convert a US ring size to UK size?▼

Use the converter above for exact results. As a quick guide: US 5 ≈ UK J½, US 6 ≈ UK L½, US 7 ≈ UK N½, US 8 ≈ UK P½, US 9 ≈ UK R½, US 10 ≈ UK T½. The pattern adds approximately 2 UK letters per US half-size increment. Note that UK letters include half sizes (e.g. J½, K½) which roughly align with US half sizes.

Does Australia use UK or US ring sizes?▼

Australia uses the British/UK system — the same letter-based A to Z+9 scale as the United Kingdom, Ireland, and New Zealand. An Australian size M is exactly the same as a UK size M (15.9mm diameter / 49.9mm circumference / equivalent to US size 6). This is because Australia adopted the British Standard BS 1283:1945 and later BS EN 28653:1993 as part of Commonwealth standardisation.

What is the difference between Japanese and Chinese ring size systems?▼

Japan has an official standard — JIS S 4700:2022 — where size 1 = 13mm inner diameter, increasing in 0.33mm steps per size. China does not have its own official national ring size standard and typically follows a Japanese-like numerical system, though Chinese retailers sometimes use EU circumference mm or even their own informal diameter-based scale. When ordering from Chinese websites, always verify the size against the diameter in mm shown in the product listing rather than relying on the number alone.