Photo by Matthieu Collin on Unsplash
You found the perfect jacket in a Harajuku boutique, grabbed what looked like your size, and it doesn’t close. Welcome to the most common frustration in Japanese shopping: the numbers on the tag don’t mean what you think they mean. Japanese clothing and shoe sizing uses different scales, different assumptions about body shape, and — crucially — different units than the US, UK, or EU systems. This guide breaks down exactly how to convert, where the conversion tables lie to you, and how to shop smart whether you’re hunting basics at a fast-fashion chain or splurging on streetwear.
Why Japanese Sizing Doesn’t Match Western Labels
Japanese apparel sizing is built around a smaller average frame and a narrower range of cuts than US or European sizing. A “Free Size” (フリーサイズ) label — common on blouses, accessories, and many Uniqlo/GU items — is really cut for a Japanese small-to-medium body, roughly US 2–6 or UK 6–10. If you’re outside that range, Free Size will not be free. Letter sizes (S/M/L/XL) also run noticeably smaller than their US equivalents: a Japanese L is closer to a US M in most brands. There’s no universal offset, though — it varies by brand and even by garment type within the same brand, so treat every chart below as a starting point, not gospel.
Women’s Clothing: The Numbers Game
Japanese women’s sizing shows up two ways: letters (S/M/L) and odd numbers (5/7/9/11/13), the latter common in department stores and office wear. Rough conversions:
- Japan 5 / S ≈ US 2–4, UK 6–8, EU 34–36 (bust ~80–83cm)
- Japan 7 / M ≈ US 4–6, UK 8–10, EU 36–38 (bust ~83–86cm)
- Japan 9 / L ≈ US 8–10, UK 12–14, EU 40–42 (bust ~86–90cm)
- Japan 11–13 / LL ≈ US 12–14, UK 16, EU 44
Bra sizing adds another wrinkle: Japanese band sizes are measured in 2.5cm increments differently from US/UK, so a Japanese 70 band is roughly a US 32. Cup letters (A, B, C) are close enough to US cups but run about one letter smaller — a Japanese C is closer to a US B. If lingerie shopping is on your list, department stores like Isetan Shinjuku offer free fitting consultations (English-speaking staff available at the main store, 10am–8pm) that are worth the ten minutes.
Men’s Clothing: Where “Large” Gets Small
Men’s tops and outerwear follow a similar downward shift:
- Japan S ≈ US XS–S, chest ~86–89cm
- Japan M ≈ US S–M, chest ~89–94cm
- Japan L ≈ US M, chest ~94–99cm
- Japan XL ≈ US L, chest ~99–104cm
Sleeve length is where travelers get caught out most — Japanese cuts tend to run shorter in the arm and torso even when the chest measurement matches. If you’re tall or broad-shouldered, check the actual cm measurements printed on the tag (usually chest 身幅 and length 着丈) rather than trusting the letter. This matters especially for streetwear, where boxy, oversized cuts are the house style — brands like those covered in our guide to Harajuku’s streetwear boutiques (BAPE, Neighborhood, Human Made) often size generously on purpose, so a Japanese M can fit like a Western L — always try before buying, since resale prices on these labels make returns painful.
Shoes: Centimeters Are Your Friend
Shoe sizing is actually the easiest category to convert, because Japan uses straight centimeter measurements (foot length) instead of an arbitrary numbering system. If you know your foot length in cm, you’re set. Rough equivalents:
- 22cm ≈ US women’s 5 / UK 2.5 / EU 35
- 23cm ≈ US women’s 6 / UK 3.5 / EU 36
- 24cm ≈ US women’s 7 / men’s 6 / UK 5.5 / EU 38
- 25cm ≈ US men’s 7 / UK 6.5 / EU 40
- 26cm ≈ US men’s 8 / UK 7.5 / EU 41
- 27cm ≈ US men’s 9 / UK 8.5 / EU 42
- 28cm ≈ US men’s 10 / UK 9.5 / EU 43
Two catches: Japanese lasts tend to be cut narrower through the heel and midfoot even when the length matches, so a snug 26cm doesn’t necessarily mean you need 26.5cm — it might mean you need a wider brand. Also, width is rarely labeled on Western sneakers sold in Japan, so always ask to try the display shoe. Our guide to ABC Mart covers how to navigate Japan’s biggest shoe chain, where staff keep a cm-measuring foot gauge (フットメジャー) at the counter — use it rather than guessing, since it takes 30 seconds and removes all doubt.
Where to Shop by Budget
Budget: GU and Uniqlo basics run ¥990–¥3,990 for tops and ¥2,990–¥4,990 for bottoms, with generous size runs (XS–3XL in many styles) and clear size charts posted in-store. Our breakdown of GU, Uniqlo’s trendier sister brand, is a good primer if you haven’t shopped there before. Mid-range: Department store floors (Isetan, Takashimaya, Hankyu) carry domestic brands from ¥8,000–¥25,000 with tailoring services on-site — hemming typically costs ¥1,000–¥2,000 and takes same-day to a few days. Splurge: Flagship streetwear stores in Harajuku and Shibuya sell limited hoodies and jackets from ¥15,000–¥40,000; because these run in small batches and rarely restock, nail your size conversion before you go rather than hoping for an exchange later.
Common Mistakes to Avoid
- Assuming your home size number applies. A US size 8 and a Japanese size 8 are not remotely the same garment — Japan’s numbered system (5/7/9/11) is its own scale, not a direct match to US numbered sizing.
- Trusting “Free Size” outside the narrow range it’s cut for. If you’re above roughly a US 8/UK 12 or below a US 2/UK 6, try it on before committing.
- Ignoring shoe width. Length in cm will usually be right; fit through the forefoot and heel is the variable that trips people up.
- Shopping during Golden Week (late April–early May) or New Year’s expecting calm fitting rooms — both are peak domestic travel periods and stores get crowded fast. January and July bring the best seiru (セール) end-of-season sales, with markdowns of 30–50% at both fast-fashion and department stores.
- Not carrying your own measurements. Write your chest/bust, waist, and foot length in cm on your phone before the trip — it’s faster than converting on the spot and far more reliable than size letters alone.
Getting There and Timing Your Trip
Harajuku’s Takeshita Street and Cat Street shops generally open 11am–8pm; department stores like Isetan Shinjuku and Takashimaya run 10am–8pm. Weekday mornings right after opening are the quietest time to get unhurried fitting-room access and attentive staff. If you’re coming in from Haneda, see our guide on getting from Haneda Airport to the city to plan the fastest route into Shibuya or Shinjuku before the shops get busy.