International conversions Nov 12, 2026 4 min read
Bra Size Conversion: US to Japan
Japanese bras use cm bands (65, 70, 75) like EU. Cup letters match US through C. JP brands often run band size smaller — size up 1 band when ordering.
The Chart
| US Band | JP Band (cm) | US Cup → JP Cup |
|---|---|---|
| 30 | 65 | A=A B=B |
| 32 | 70 | C=C D=D |
| 34 | 75 | DD=E |
| 36 | 80 | DDD=F |
| 38 | 85 | G=G |
| 40 | 90 | H=H |
FAQs
Why JP bands run small?
Japanese baseline body measurements are slimmer than US. A US-made size 75A and a Japanese-made 75A may have slightly different actual underbust circumference. Try sizing up one band when ordering Japanese brands.
Wacoal — Japanese or US sizing?
Wacoal Japan uses Japanese sizing. Wacoal America uses US sizing. They're related companies but the local brand sizes match local market norms. Check origin.
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