Reviewed
30J (UK 30GG) bra size
A 30J has a 30-inch band and a J cup, about 10 inches between band and bust. In the UK it is 30GG, in Australia 8GG and in Europe 65J.
- US
- 30J
- UK
- 30GG
- AU
- 8GG
- EU
- 65J
- FR
- 80J
Also fits (sister sizes): 28K firmer band · 32I looser band · all same-volume sizes ↓
30J measurements
- Snug underbust
- 30–31 in · 76–79 cm
- Bust, fullest part
- about 40 in · 100–103 cm
- Cup difference
- 10 in (J cup)
These are starting points from the band-and-cup method. Brands differ by about a size, so a two-minute measurement beats any chart.
30J sister sizes
Same cup volume, different band. If a 30J band feels too loose, go down a band and up a cup; if it feels tight, go up a band and down a cup.
If a 30J doesn't fit
- Band rides up at the back
- Try 28K
- Band digs in, cups fit
- Try 32I
- Spilling over the cups
- Try 30K
- Cups gape or wrinkle
- Try 30I
Not sure what's wrong? Run through the 4-point fit check.
30J questions
What is the sister size of 30J?
28K (one band down, one cup up) and 32I (one band up, one cup down). Sister sizes hold the same cup volume on a different band.
What is 30J in UK, Australian and European sizes?
UK 30GG, Australia 8GG, Europe 65J and France 80J. US and UK cup letters match up to DD and then split.
What measurements are a 30J?
A snug underbust of about 30–31 in (76–79 cm) and a bust of about 40 in (100–103 cm). Measure with the tape level and use the calculator for an exact result.
Is 30J a big size?
30J has a very full cup volume for a 30 band. Cup letters only mean something next to the band: a 30J holds the same as 28K or 32I.