Shoe Size Converter
Instantly convert shoe sizes across international sizing systems. Enter your size in any system (US, UK, EU, or foot length in cm) and see the equivalent in all other systems for both men and women.
Shoe sizing is a mess. Different countries use different scales, the same nominal size differs between brands, men's and women's scales are offset within the same region, and the foot itself can change size with age, weight, pregnancy, and time of day. This converter standardizes the four most common scales — US, UK, EU, and centimeters — so you can buy international shoes online without guessing.
Enter your size in any one system and the calculator returns the equivalent in the others, separately for men's and women's scales. The conversion uses standard published tables; individual brand variation can shift fit by half a size in either direction even at the same nominal size.
The single most reliable measurement is foot length in centimeters. Trace your foot on paper while standing (full body weight loaded), measure heel to longest toe, and use that to look up the correct size in whichever scale you're shopping. Allow extra room for thicker socks, summer swelling, or wide feet.
Inputs
Results
UK Size
9.5
EU Size
43.0
CM (Japan)
26.5 cm
All Size Conversions
| Sizing System | Size |
|---|---|
| US Men's | 10.0 |
| US Women's | 11.5 |
| UK | 9.5 |
| EU | 43.0 |
| CM (Japan) | 26.5 |
Formula
How to use this calculator
- Choose gender. Men's and women's scales differ within each country.
- Enter your size in the system you know.
- Read the equivalent in other systems. Conversions are accurate to about ±0.5 size.
- When in doubt, measure your foot in cm. Stand on paper, trace the outline, measure heel to longest toe. That number is the most reliable cross-brand reference.
- For online orders, check brand-specific size charts. Even within the U.S. system, a Nike 10 fits differently from an Adidas 10.
Worked examples
Buying European sneakers
You wear US Men's 10. Equivalent EU size: ~43.5. Some EU brands list 43 and 44; pick 44 for narrow feet (43 will be tight) or 43 for wide feet (44 will slip). Half-size differences in EU are uncommon — many EU brands offer only whole sizes.
Cross-gender purchase
A women's US 9 = roughly men's US 7.5. This matters when buying men's-styled or unisex sneakers — a women's size doesn't exist in those lines, so you'd order the men's 7.5 equivalent.
When to use this calculator
Use this whenever you shop online from a brand using a different sizing system, or when buying gifts where you only know one size. For in-store purchases, just try them on — the most reliable test is walking in the shoe.
A few situational notes: - Athletic shoes typically run 0.5–1 size large compared to dress shoes from the same brand - Time of day matters: feet swell roughly 5% by evening; measure or shop in the afternoon - Wide feet may need to size up half a size, OR seek out width-specific options (D = standard men's, EE = wide; B = standard women's, D = wide) - Children's sizing is its own scale (US Toddler 1–13.5, then US Youth/Big Kid 1–7), with a roughly continuous mapping into adult sizes around age 12
For ring and clothing sizing, see the ring size and dress size calculators in this category.
Common mistakes to avoid
- Assuming US and UK sizes are the same. They're close but offset by about 1 size.
- Mixing men's and women's sizes. A women's 8 is not a men's 8 — it's about a men's 6.5.
- Using EU sizes by simple math. The Paris point system isn't a clean function of cm; lookup tables are more reliable than formulas.
- Buying based on length only. Width matters too, and brands vary substantially in width even at the same nominal size.
- Measuring feet sitting down. Foot size changes when you stand and the foot loads weight. Always measure standing.
Frequently Asked Questions
Sources & further reading
- How to measure shoe size — American Podiatric Medical Association