Clothing Size Converter — JP, US, UK, EU & Intl (S–XL)
Convert international clothing sizes for women’s dresses & tops, men’s shirts (collar) and suits between JP, US, UK, EU and S–XL — pick your size in one system and see all the others, with a full chart.
🔒 Runs entirely in your browser. Your input and output are never sent to a server or stored — fully private.
Sizes are standards-based approximations and vary a lot between brands and cuts — always check the item’s own size chart before buying. Men’s shirt sizes are collar measurements; suit sizes are chest-based.
Full chart
About this tool
Shopping across borders gets confusing fast: a Japanese 9号, a US 6, a UK 10 and an EU 38 can all be roughly the same dress. This international clothing size converter lines up JP, US, UK and EU sizes — plus the familiar S–XL letters — for women's dresses and tops, men's shirts (by collar size) and men's suits. Pick your known size in any system and read the equivalents across the row. The tables are built into the page and everything works in your browser, with nothing sent anywhere, so you can compare sizes right in the fitting room or mid-checkout.
Frequently asked questions
The converted size didn't fit — is the table wrong?
Probably not — sizing genuinely varies by brand, cut and country of manufacture. Two "US 6" dresses from different labels can differ by several centimetres, and fast-fashion, luxury and Japanese domestic brands each run differently. Treat any conversion table, including this one, as a standards-based starting point. Before buying, always check the garment's own size chart with actual measurements (bust, waist, collar in cm or inches) and compare against a piece of clothing that fits you well.
What is vanity sizing?
Vanity sizing is the gradual inflation of size labels: over the decades, brands — especially in the US — have attached smaller numbers to bigger garments so shoppers feel slimmer. A dress labelled US 8 today can be larger than a US 12 from the 1970s, and the drift differs by brand and price segment. This is a big reason why cross-country conversions can only ever be approximate, and why measurements in centimetres or inches are far more trustworthy than the number on the tag.
How do men's shirt and suit sizes work across countries?
Dress shirts are sized by collar circumference: Japan and Europe use centimetres, the US and UK use inches — so a JP/EU 39 collar equals a US/UK 15.5. Suits are sized by chest: US and UK share inch-based numbers (a 38 is a 38-inch chest), while Europe uses roughly that number plus 10 in metric sizing (EU 48). Japan often adds a letter for body type — Y for slim, A for regular, AB and B for fuller builds — so a Japanese A5 is close to an EU 48.