About Japan Bra Sizing
Japanese bands use cm in 5-cm steps (60, 65, 70, 75...) — same as EU. Cup letters follow the EU single-letter progression (no DD).
Japan Band & Cup Reference
Here is the complete band and cup reference for Japan sizing alongside the US equivalent for easy conversion.
| Japan band | US band equivalent | Japan cup letters |
|---|---|---|
| 60 cm | 24 | AA · A · B · C · D · E · F · G |
| 65 cm | 26 | AA · A · B · C · D · E · F · G |
| 70 cm | 28 | AA · A · B · C · D · E · F · G |
| 75 cm | 30 | AA · A · B · C · D · E · F · G |
| 80 cm | 31 | AA · A · B · C · D · E · F · G |
| 85 cm | 33 | AA · A · B · C · D · E · F · G |
| 90 cm | 35 | AA · A · B · C · D · E · F · G |
| 95 cm | 37 | AA · A · B · C · D · E · F · G |
| 100 cm | 39 | AA · A · B · C · D · E · F · G |
Cup Letter Differences
The Japan system uses these cup letters in order from smallest to largest:
AA → A → B → C → D → E → F → G → H → I → J → K
How to Convert From Japan to Other Systems
To convert your Japan bra size to another system, change the band first, then the cup:
- Band conversion: divide your cm band by 2.54 to get the inch equivalent for US/UK.
- Cup conversion: A–D is universal. Past D, US uses DD/DDD, UK uses E/F/FF, and EU/JP/BR use single letters E/F/G or numeric 1/2/3.
Best Brands Sold in Japan
Triumph, Chantelle, Simone Pérèle, Wacoal, and Aubade are popular across Japan.