Shoe Size Converter
Shoe sizes look universal but are not: a US 8, a UK 7 and an EU 41 are all roughly the same foot, and Japan sizes the shoe by the foot length in centimetres. Buying shoes across borders means converting, and a single point of error means a shoe that does not fit. This converter starts from a measured foot length — the one thing every system shares — and returns the size in the system your region uses.
The target region is chosen automatically from the language you are viewing the site in: English visitors get US sizing, German and French visitors get EU, Japanese visitors get JP, Thai visitors get UK. You can override it with the selector. Measure your longest foot in centimetres (ideally in the evening, standing, with the sock you will wear), enter it, and read the size for your region.
It is the conversion that makes cross-border shoe shopping safe — the one number every system shares is the physical foot, and starting from it means a US, UK, EU or JP size that actually fits instead of a guess.
Enter your values to see the result.
How this is calculated
The converter starts from a measured foot length in centimetres, the one measurement every sizing system derives from. Each system is then computed from that foot length using its standard formula. The US men’s size is 3 × (foot length in inches) − 22; US women’s is 3 × inches − 21; UK is 3 × inches − 23 (roughly one size below US men’s); EU is 1.5 × (foot length + 2 cm), the Paris-point system with a 2 cm allowance; JP is the foot length in centimetres directly; China uses the EU-equivalent formula; Mexico is 3 × inches − 20.
The target region is chosen automatically from the site language you are viewing — English defaults to US, German, French, Spanish, Italian and Portuguese to EU, Japanese to JP, Thai to UK — because shoe sizing is regional and a visitor almost always wants the system used where they live or shop. A selector lets you override the default to convert into any other system, so the tool works for cross-border shopping regardless of where you are.
The formulas give the standard mapping, but shoe sizing is not perfectly standardised across brands. Lasts (the foot-shaped forms shoes are built on) differ, athletic shoes often run large, and dress shoes run small. The result is an accurate guide to the right size band; for a brand you know, check its own size chart, and when between sizes, size up for athletic shoes and consider the brand’s fit for dress shoes.
Worked example
Your foot measures 25.5 cm. You are viewing the site in English (US default) but want the EU size.
- 1Inches = 25.5 ÷ 2.54 = 10.04.
- 2US men = 3 × 10.04 − 22 = 8.1 ≈ US 8.
- 3EU = 1.5 × (25.5 + 2) = 41.25 ≈ EU 41.
- 4JP = 25.5 (foot length in cm). UK ≈ 7.
- 5Switch the selector to EU and the headline result reads EU 41.
Frequently asked questions
- How do I measure my foot length?
- Stand on a sheet of paper, mark the heel and the tip of the longest toe, and measure between the marks in centimetres. Measure both feet and use the larger one. Do it in the evening — feet spread slightly over the day — and with the socks you plan to wear.
- Why does the default region change with my language?
- Because shoe sizing is regional. A visitor reading the site in German almost always wants EU sizes; one reading in Japanese wants JP. The converter defaults to the region that matches your site language, then lets you switch to any other system with the selector.
- Are the converted sizes exact?
- They are derived from standard formulas applied to your foot length, so they are accurate guides. Brands cut differently and lasts vary, so treat the result as a starting point and check the brand’s own size chart when you can.
- Why does the default region change when I switch the site language?
- Because shoe sizing is regional. A German visitor almost always wants EU sizes; a Japanese visitor wants JP. The converter reads your site language and defaults to the matching region, so the first result you see is the locally correct one. You can still switch to any system with the selector.
- Should I measure both feet?
- Yes. Most people have one foot slightly longer than the other, sometimes by half a size or more. Measure both feet standing, in the evening, and use the longer measurement — a shoe that fits the longer foot will fit the shorter one too, while the reverse is not true.
Related calculators
Method: standard shoe-size formulas from measured foot length (US, UK, EU/Paris points, JP, China, Mexico). Region defaults follow the site language. Last updated: September 2026.
These results are general estimates from established formulas and conversion factors. Paint coverage, tile yields, concrete volumes, fuel economy, oven behaviour and clothing and shoe sizes vary by product, surface, vehicle, oven and brand. Always confirm with your supplier, the product label or the brand’s own size chart before buying or acting on a calculation.