Shoe Size Conversion

Convert Shoe Sizes Between Any System

Shopping for shoes internationally — whether from a European luxury brand, a Japanese sneaker label, or a UK heritage boot maker — means navigating sizing systems that don't align intuitively. A US men's 10 is a UK 9.5, an EU 44, and a 28 cm. Get it wrong and you're dealing with returns, shipping costs, and the disappointment of shoes that don't fit.

Our converter translates instantly between US (separate men's and women's scales), UK (separate men's and women's), European (EU — unisex), and centimeter/Mondopoint (used in Japan, Korea, and military specifications). Enter your known size in any system and see all equivalents.

Quick reference tables:
Men's: US 8 = UK 7.5 = EU 41 = 26 cm. US 9 = UK 8.5 = EU 42.5 = 27 cm. US 10 = UK 9.5 = EU 44 = 28 cm. US 11 = UK 10.5 = EU 45 = 29 cm. US 12 = UK 11.5 = EU 46 = 30 cm.
Women's: US 6 = UK 4 = EU 36.5 = 23 cm. US 7 = UK 5 = EU 38 = 24 cm. US 8 = UK 6 = EU 39 = 25 cm. US 9 = UK 7 = EU 40 = 26 cm. US 10 = UK 8 = EU 41.5 = 27 cm.

How Each Sizing System Works

US sizing maintains separate scales for men and women. Women's sizes are approximately 1.5 numbers higher than men's for the same foot length — a women's US 8.5 fits the same length foot as a men's US 7. Children's sizes use yet another scale, transitioning to adult sizes around US kids' 13 (which becomes approximately adult women's 1 or men's 1, depending on the brand). The US system is based on the Brannock device, which measures foot length in inches with each full size representing 1/3 inch (approximately 8.47mm). Half sizes are 1/6 inch (~4.23mm).

UK sizing is similar to US but offset differently. UK men's sizes are approximately 0.5–1 size smaller than US men's (US 10 = UK 9.5). UK women's sizes are approximately 2 sizes smaller than US women's (US 8 = UK 6). Each UK size represents 1/3 inch, based on the centuries-old British "barleycorn" system.

European (EU) sizing uses the Paris point system, where each full size equals 2/3 centimeter (6.67mm). EU sizes are unisex — an EU 42 is the same regardless of whether it's labeled for men or women (though the shoe's width and shape may differ). The unisex nature of EU sizing makes it the most logical system for international commerce.

Centimeter (CM) and Mondopoint measure foot length directly — the most objective and precise system. Japanese shoe sizes are in centimeters (a size 27 shoe fits a 27 cm foot). Mondopoint (used by NATO and some industrial footwear) specifies both length and width in millimeters (e.g., 270/105 means 270mm long, 105mm wide).

How to Measure Your Feet at Home

Step 1: Stand on a sheet of paper with your heel against a wall. Wear the type of socks you'll wear with the shoes you're sizing for. Step 2: Mark the tip of your longest toe on the paper. For most people this is the big toe, but approximately 20% of people have a second toe that's longer (Morton's toe). Step 3: Measure from the wall to the mark in centimeters. Step 4: Measure both feet. Most people have one foot that's 2–5mm longer than the other. Always size for the larger foot. Step 5: Measure in the afternoon or evening. Feet swell throughout the day — they can be up to half a size larger in the evening compared to morning.

Width Sizing: The Forgotten Dimension

Length gets all the attention, but width determines comfort just as much. Standard width designations: Women's standard is B, men's standard is D. The scale runs from AAAA (narrowest) through EEEE (widest). Each width increment represents approximately 3/16 inch (4.8mm) at the ball of the foot.

Women's widths: AA = narrow. B = standard/medium. D = wide. EE = extra wide. Men's widths: B = narrow. D = standard/medium. E or EE = wide. EEE or EEEE = extra wide.

If shoes in your correct length feel tight across the ball of the foot, try a wider width rather than a longer size. Going up a full size adds length you don't need without adequately addressing width. New Balance offers the widest range of width options (from 2A to 6E). Nike tends to run narrow.

Brand-Specific Sizing Variations

There is no enforced international standard for shoe sizing — each brand creates their own lasts (three-dimensional foot molds) and interprets sizing differently. Known quirks: Nike tends to run true to slightly small — size up 0.5 if between sizes. Adidas tends to run 0.5 size small. New Balance runs true to size with generous width options. Converse Chuck Taylors run large — most people size down 0.5 to 1 full size. Dr. Martens run large — typically 0.5–1 size down. The safest approach when trying a new brand: order from a retailer with free returns, order your calculated size plus the half size above, keep the better fit.

Children's Shoe Sizing

US children's sizes run from 0 (infant) through 13 (pre-teen), then transition to adult sizes. Children's 13 is followed by adult 1. Children's feet grow approximately 1 mm per month — roughly one full shoe size every 3–4 months for toddlers, slowing to one size every 4–6 months for school-age children. Buying shoes with a thumb's-width of space beyond the longest toe (~1 cm) accommodates growth. Professional fitting is especially valuable for children's first walking shoes and school shoes.