Shoe Size Converter

EU sizes run higher than US: a US men's 9 is about EU 42, and a US women's 8 is about EU 38.5. UK sizes sit just below US (men subtract about 0.5, women about 2). These are approximations built from a typical offset between systems — the most reliable guide is always the foot length, which the calculator shows alongside the converted sizes.

Unlike a metric-to-imperial length conversion, shoe sizing has no single physical standard behind it. US sizing grew out of the Brannock Device, a foot-measuring tool introduced in 1925 that maps foot length to a size number in third-inch (8.46 mm) steps. EU (Paris point) sizing instead steps in two-thirds of a centimeter. UK sizing uses yet another historical scale, based on barleycorns (a third of an inch) counted from a nominal starting point. Three different step sizes, three different zero points — there is no clean multiplication that turns one into another exactly, which is why every cross-standard conversion, including this one, is an approximation.

Because every brand fits differently on top of the sizing-system differences above, measure your foot length (heel to longest toe) and compare it with the specific maker's own size chart when one is available. A few millimeters can shift the size by a full number. Measure at the end of the day, when feet are slightly larger from normal daily swelling, and always size from the bigger foot — most people's feet are not perfectly symmetrical.

Length is only half the fit. Width is sized separately, often on a letter scale (roughly AAA/AA/A/B/C/D/E/EE/EEE, narrow to wide, with the "average" letter differing between men's and women's charts). Two shoes can share the same length size and still fit completely differently if their width doesn't match your foot — a detail no length-only converter, including this one, can capture. Brands vary in which widths they even stock, which is part of why a single "true size" often does not exist across a wardrobe.

Kids' shoes are not simply small adult sizes — most brands run a separate youth or toddler scale that starts over near a US size 0 or 1 rather than continuing down from adult numbers, then transitions into adult sizing somewhere in the young-teens size range. A size chart built for adult feet, including the approximations this calculator applies, does not carry over correctly to children's footwear — always use the maker's dedicated kids' chart instead.