UK to US Shoe Size Converter

For men's footwear the conversion is the easier of the two: take your UK size and add about half a size to reach the equivalent US size. A men's UK 8 lands at about US 8.5, a UK 9 at about US 9.5, and a UK 10 at about US 10.5. Half sizes carry across the same way, so a UK 9.5 sits at roughly US 10. The reason the offset is so small is that both scales are built on the old barleycorn unit and the men's ranges were aligned with only a half-step shift between the two countries.

In practice that means a British man who normally buys a UK 9 should reach for a US 9.5 when ordering from an American brand. If you want to skip the mental arithmetic, the converter above already does the lookup for you, including the half sizes that the simple "add a half" rule still rounds over. If you are curious about why the two systems landed half a size apart in the first place, the full UK vs US shoe sizes guide walks through the barleycorn measurement and its history in detail.

Women's sizing has a wider gap. Where men add about half a size, women add roughly two sizes to move from UK to US. A women's UK 5.5 converts to about US 7.5, a UK 6 to about US 8, and a UK 4 to roughly US 6. That larger jump catches a lot of shoppers out, because it is tempting to assume the UK-to-US offset is the same for everyone. It is not — the women's scale and the men's scale were aligned to the two countries differently, which is why the chart above shows women climbing faster than the half-step shift men see.

The mismatch is also why a US women's size sits about one and a half sizes above the equivalent US men's size. If you find a shoe listed only in US men's numbers and you usually buy women's, convert your UK size to US women's with the table first, then subtract roughly 1.5 to land on the men's figure. Because the gap is approximate and lasts differ between models, treat the result as a starting point and confirm against the foot-length column rather than trusting the number alone.

British retailers and home-grown brands almost always print the UK size on the box and the insole, even when they sell internationally. American sites usually default to US numbers, sometimes with the EU size alongside. The trouble starts when a listing shows only one system: if you spot a lone UK number on a US-facing store, add the offset for your gender — about half a size for men, around two for women — before you commit, or sidestep the guesswork entirely by matching the foot-length column in the chart above to your own measured length.

The single most common ordering mistake is converting on the wrong gender tab. The same UK number maps to a different foot length on the women's and men's scales, so a women's UK 6 and a men's UK 6 are not the same shoe. Confirm which scale a retailer is using, set the converter to match, and cross-check the centimetre figure whenever a brand is known to run large or small. Foot length in centimetres is the one value that never shifts between countries, which makes it the safest anchor when you are buying unseen across the Atlantic.