💍 Jewellery
US 13 to JP
Converting a US ring size of 13 gives JP 27, based on an inner circumference of about 69.7 mm. The complete cross-system chart is below.
US 13 = JP 27
Inner circumference ≈ 69.7 mm · diameter ≈ 22.2 mm · EU/ISO 70
Full cross-system equivalents for this ring size:
| US | UK | EU | JP | Circ (mm) | Diam (mm) |
|---|---|---|---|---|---|
| 11.5 | W½ | 66 | 24 | 65.9 | 21.0 |
| 12 | X½ | 67 | 25 | 67.2 | 21.4 |
| 12.5 | Y½ | 68 | 26 | 68.5 | 21.8 |
| 13 | Z½ | 70 | 27 | 69.7 | 22.2 |
⚠️ UK letters vary by jeweller: half-letter conventions differ slightly between brands. The EU/ISO number equals the inner circumference in mm, so it's the most reliable cross-check. If between sizes, order the larger.
Need a different size? Use the live ring size converter to convert any value, including a mm measurement.
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What is US ring size 13 in JP?
US 13 is equivalent to JP 27 (inner circumference ~69.7 mm, EU/ISO 70, 22.2 mm diameter).