Converting UK Sizes to US
If you are shopping on a US-based retailer and your size is in UK, the conversion is straightforward: US Men's ≈ UK + 1 and US Women's ≈ UK + 2. Both systems are based on the barleycorn unit (⅓ inch per size), so the relationship is linear with a fixed offset.
This rule holds consistently across the adult size range (UK 3 to UK 13). The underlying formulas: UK = 3 × foot (in) − 23, US Men = 3 × foot (in) − 22, US Women = 3 × foot (in) − 21.
UK to US Conversion Chart
| UK | US Men's | US Women's | EU | cm |
|---|---|---|---|---|
| 3 | 4 | 5 | 35 | 22 |
| 3.5 | 4.5 | 5.5 | 36 | 22.4 |
| 4 | 5 | 6 | 36 | 22.9 |
| 4.5 | 5.5 | 6.5 | 37 | 23.3 |
| 5 | 6 | 7 | 38 | 23.7 |
| 5.5 | 6.5 | 7.5 | 38 | 24.1 |
| 6 | 7 | 8 | 39 | 24.6 |
| 6.5 | 7.5 | 8.5 | 39 | 25 |
| 7 | 8 | 9 | 40 | 25.4 |
| 7.5 | 8.5 | 9.5 | 41 | 25.8 |
| 8 | 9 | 10 | 41 | 26.2 |
| 8.5 | 9.5 | 10.5 | 42 | 26.7 |
| 9 | 10 | 11 | 43 | 27.1 |
| 9.5 | 10.5 | 11.5 | 43 | 27.5 |
| 10 | 11 | 12 | 44 | 27.9 |
| 10.5 | 11.5 | 12.5 | 45 | 28.4 |
| 11 | 12 | 13 | 45 | 28.8 |
| 11.5 | 12.5 | 13.5 | 46 | 29.2 |
| 12 | 13 | 14 | 46 | 29.6 |
| 12.5 | 13.5 | 14.5 | 47 | 30.1 |
| 13 | 14 | 15 | 48 | 30.5 |
Worked Examples
- UK 9 → US Men's 10, US Women's 11: foot = 27.1 cm. US Men = 9 + 1 = 10.
- UK 5 → US Men's 6, US Women's 7: foot = 23.7 cm.
- UK 11 → US Men's 12: foot = 28.8 cm.
Common Mistakes
- Adding 1 for women: The +1 rule is for men's. For women's, add 2 to the UK size.
- Confusing UK with Australian sizing: Australian men's sizes equal UK sizes. Australian women's are typically UK + 2 (same as US Women's), but some brands differ.
- Applying adult rules to children: UK and US children's sizes use a separate formula with a different offset.
Enter a UK size in the shoe size converter to see US, EU, Japan, and China equivalents instantly.