30J bra size — conversion chart, sister sizes & brands
A 30J bra (US notation) in every regional standard. The same band-and-cup, labelled eight different ways.
| US | UK | EU | FR | IT | AU | JP | IN |
|---|---|---|---|---|---|---|---|
| 30J | 30GG | 65J | 80J | 65J | 8GG | 65J | 30GG |
Band conversions are exact; cup fit still varies by brand, style, and body — a conversion is a starting point, not a guarantee.
Sister sizes of 30J
Sister sizes hold the same cup volume with a different band — the quickest fix when a band feels too tight or too loose.
Not sure you're a 30J? Two measurements, two minutes — free, nothing stored.
Check my size →Brands that make J-cup bras
30J FAQ
- What is 30J in EU sizing?
- 30J (US) is EU 65J. In UK sizing it is 30GG. Band conversions are exact; cup fit still varies by brand, style, and body — a conversion is a starting point, not a guarantee.
- What are the sister sizes of 30J?
- 32I — same cup volume, different band.
- Is 30J the same in every brand?
- No. A 30J can fit differently between brands because of pattern, fabric and cup shape. Use it as a starting point and try a sister size when switching brands.