Sizing Tips
Ring Size Chart for UK Rings
Our size chart is ideal for anyone purchasing a ring in UK sizes, as it provides the converted sizes in all major international systems. With our chart, you can easily find the corresponding US, EU, IT, UK, East Asian and circumference measurements for each UK size:
| UK | Circum. | Diam. | ISO / EU | US | IT | East Asia |
|---|---|---|---|---|---|---|
| A | 37.5mm (1.48") | 11.9mm | 40 | 0 ½ | 0 | 1 |
| A 1/2 | 38.1mm (1.50") | 12.1mm | 40 | 0 ¾ | 0 | 1 |
| B | 38.8mm (1.53") | 12.3mm | 40 | 1 | 0 | 1 |
| B 1/2 | 39.4mm (1.55") | 12.5mm | 40 | 1 ¼ | 0 | 1 |
| C | 40.0mm (1.57") | 12.7mm | 40 | 1 ¼ | 0 | 1 |
| C 1/2 | 40.6mm (1.60") | 12.9mm | 41 | 1 ½ | 1 | 1 |
| D | 41.3mm (1.62") | 13.1mm | 41 | 1 ¾ | 1 | 1 |
| D 1/2 | 41.9mm (1.65") | 13.3mm | 42 | 2 | 2 | 2 |
| E | 42.5mm (1.67") | 13.5mm | 42 | 2 ¼ | 2 | 3 |
| E 1/2 | 43.1mm (1.70") | 13.7mm | 43 | 2 ½ | 3 | 3 |
| F | 43.8mm (1.72") | 13.9mm | 44 | 2 ¾ | 4 | 4 |
| F 1/2 | 44.4mm (1.75") | 14.1mm | 44 | 3 | 4 | 4 |
| G | 45.0mm (1.77") | 14.3mm | 45 | 3 ¼ | 5 | 5 |
| G 1/2 | 45.6mm (1.80") | 14.5mm | 46 | 3 ½ | 6 | 6 |
| H | 46.3mm (1.82") | 14.7mm | 46 | 3 ¾ | 6 | 6 |
| H 1/2 | 46.9mm (1.85") | 14.9mm | 47 | 4 | 7 | 7 |
| I | 47.5mm (1.87") | 15.1mm | 47 | 4 ¼ | 7 | 7 |
| I 1/2 | 48.1mm (1.89") | 15.3mm | 48 | 4 ½ | 8 | 8 |
| J | 48.8mm (1.92") | 15.5mm | 49 | 4 ¾ | 9 | 9 |
| J 1/2 | 49.4mm (1.94") | 15.7mm | 49 | 5 | 9 | 9 |
| K | 50.0mm (1.97") | 15.9mm | 50 | 5 ¼ | 10 | 10 |
| K 1/2 | 50.6mm (1.99") | 16.1mm | 51 | 5 ½ | 11 | 10 |
| L | 51.3mm (2.02") | 16.3mm | 51 | 5 ¾ | 11 | 11 |
| L 1/2 | 51.9mm (2.04") | 16.5mm | 52 | 6 | 12 | 12 |
| M | 52.5mm (2.07") | 16.7mm | 52 | 6 ¼ | 12 | 12 |
| M 1/2 | 53.1mm (2.09") | 16.9mm | 53 | 6 ½ | 13 | 13 |
| N | 53.8mm (2.12") | 17.1mm | 54 | 6 ¾ | 14 | 13 |
| N 1/2 | 54.4mm (2.14") | 17.3mm | 54 | 7 | 14 | 14 |
| O | 55.0mm (2.17") | 17.5mm | 55 | 7 ¼ | 15 | 15 |
| O 1/2 | 55.6mm (2.19") | 17.7mm | 56 | 7 ½ | 16 | 15 |
| P | 56.3mm (2.21") | 17.9mm | 56 | 7 ¾ | 16 | 16 |
| P 1/2 | 56.9mm (2.24") | 18.1mm | 57 | 8 | 17 | 16 |
| Q | 57.5mm (2.26") | 18.3mm | 57 | 8 ¼ | 17 | 17 |
| Q 1/2 | 58.1mm (2.29") | 18.5mm | 58 | 8 ½ | 18 | 18 |
| R | 58.8mm (2.31") | 18.7mm | 59 | 8 ¾ | 19 | 18 |
| R 1/2 | 59.4mm (2.34") | 18.9mm | 59 | 9 | 19 | 19 |
| S | 60.0mm (2.36") | 19.1mm | 60 | 9 ¼ | 20 | 19 |
| S 1/2 | 60.6mm (2.39") | 19.3mm | 61 | 9 ½ | 21 | 20 |
| T | 61.3mm (2.41") | 19.5mm | 61 | 9 ¾ | 21 | 20 |
| T 1/2 | 61.9mm (2.44") | 19.7mm | 62 | 10 | 22 | 21 |
| U | 62.5mm (2.46") | 19.9mm | 62 | 10 ¼ | 22 | 22 |
| U 1/2 | 63.1mm (2.49") | 20.1mm | 63 | 10 ½ | 23 | 22 |
| V | 63.8mm (2.51") | 20.3mm | 64 | 10 ¾ | 24 | 23 |
| V 1/2 | 64.4mm (2.53") | 20.5mm | 64 | 11 | 24 | 23 |
| W | 65.0mm (2.56") | 20.7mm | 65 | 11 ¼ | 25 | 24 |
| W 1/2 | 65.6mm (2.58") | 20.9mm | 66 | 11 ½ | 26 | 25 |
| X | 66.3mm (2.61") | 21.1mm | 66 | 11 ¾ | 26 | 25 |
| X 1/2 | 66.9mm (2.63") | 21.3mm | 67 | 12 | 27 | 26 |
| Y | 67.5mm (2.66") | 21.5mm | 67 | 12 ¼ | 27 | 26 |
| Y 1/2 | 68.1mm (2.68") | 21.7mm | 68 | 12 ½ | 28 | 27 |
| Z | 68.8mm (2.71") | 21.9mm | 69 | 12 ¾ | 29 | 28 |
| Z1 | 70.0mm (2.76") | 22.3mm | 70 | 13 ¼ | 30 | 29 |
| Z1 1/2 | 70.6mm (2.78") | 22.5mm | 71 | 13 ½ | 31 | 29 |
| Z2 | 71.3mm (2.81") | 22.7mm | 71 | 13 ¾ | 31 | 30 |
| Z2 1/2 | 71.9mm (2.83") | 22.9mm | 72 | 13 ¾ | 32 | 31 |
| Z3 | 72.5mm (2.85") | 23.1mm | 72 | 14 | 32 | 31 |
| Z3 1/2 | 73.1mm (2.88") | 23.3mm | 73 | 14 ¼ | 33 | 32 |
| Z4 | 73.8mm (2.90") | 23.5mm | 74 | 14 ½ | 34 | 32 |
US and North American Sizing
The United States, Canada, and Mexico employ a numbered system where EU sizes convert predictably. A popular EU size 54 translates to approximately US size 7, while EU 52 corresponds to US size 6. US sizing increases in quarter-size increments (6, 6.25, 6.5, 6.75, 7), spanning roughly from US size 3 (EU 44) to US size 13 (EU 70).
UK and Commonwealth Sizing
British sizing uses letters from A through Z and beyond. The conversion from EU sizing follows a clear pattern: EU size 54 equals UK size N, EU size 52 matches UK size L. This alphabetical system serves the United Kingdom, Ireland, Australia, South Africa, and New Zealand.
Italian and Mediterranean Sizing
Italian sizing, used across Italy, Spain, Netherlands, and Switzerland, typically subtracts 40 from the EU measurement. Therefore, EU size 54 becomes Italian size 14, and EU size 52 converts to Italian size 12. This consistent offset makes conversion calculations simple.
Asian Diameter-Based Systems
East and Southeast Asian countries, including Japan, China, South Korea, and parts of South America, use a diameter-based system rather than circumference. Their sizing begins at size 1 (13mm internal diameter) and increases by 0.33mm increments. To convert from EU circumference to Asian sizing, divide the EU size by π (3.14159) to get diameter, then apply the Asian size formula.
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