UK (UK) to US Women's (US W) Conversion
UK
UK shoe sizes are based on the barleycorn system — one barleycorn equals one third of an inch (8.47 mm) — where the size represents last length in barleycorns minus a fixed offset. UK Men's sizes typically run 0.5 to 1 size below the equivalent US Men's size for the same foot (UK 9 ≈ US 9.5). UK Women's sizes run approximately 2.5 sizes below US Women's. The system predates metric standardisation and remains in official use in the United Kingdom alongside EU sizing on product labels.
US Women's
US Women's shoe sizes use the same Brannock-derived scale as Men's but with a consistent offset of 1.5 sizes: Women's size 9 corresponds to Men's 7.5 for the same foot length. This offset reflects historical manufacturing conventions rather than anatomical differences — women's lasts were cut narrower and numbered separately for retail. US Women's sizes typically range from 4 to 14. A foot measuring 24.5 cm corresponds to approximately US Women's 8.5, EU 39, UK 6.5, and JP 24.5.
Frequently Asked Questions (FAQ)
How do I convert US shoe sizes to European (EU) sizes?
For men's shoes, add approximately 33 to the US size to get the EU size — for example, US Men's 9 equals EU 42. For women's shoes, add approximately 31 — US Women's 9 equals EU 40. However, these are approximations: different brands apply slightly different lasts, so always check the specific brand's size chart. Use our converter above to see all international equivalents simultaneously.
Why do shoe sizes differ so much between countries?
Shoe sizes evolved independently in different regions over centuries, each based on different measurement conventions. European sizes use the Paris Point (⅔ of a centimetre), making EU 40 equal to a foot length of about 25.8 cm. US sizes use a different last-length formula with separate scales for men and women, where a women's size is 1.5 sizes larger than a men's size for the same foot. Japanese sizes are the most intuitive — they directly measure foot length in centimetres. No international standard has ever successfully unified all systems.