Reviewed
30I (UK 30G) bra size
A 30I has a 30-inch band and a I cup, about 9 inches between band and bust. In the UK it is 30G, in Australia 8G and in Europe 65I.
- US
- 30I
- UK
- 30G
- AU
- 8G
- EU
- 65I
- FR
- 80I
Also fits (sister sizes): 28J firmer band · 32H looser band · all same-volume sizes ↓
30I measurements
- Snug underbust
- 30–31 in · 76–79 cm
- Bust, fullest part
- about 39 in · 98–100 cm
- Cup difference
- 9 in (I 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.
30I sister sizes
Same cup volume, different band. If a 30I 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 30I doesn't fit
- Band rides up at the back
- Try 28J
- Band digs in, cups fit
- Try 32H
- Spilling over the cups
- Try 30J
- Cups gape or wrinkle
- Try 30H
Not sure what's wrong? Run through the 4-point fit check.
30I questions
What is the sister size of 30I?
28J (one band down, one cup up) and 32H (one band up, one cup down). Sister sizes hold the same cup volume on a different band.
What is 30I in UK, Australian and European sizes?
UK 30G, Australia 8G, Europe 65I and France 80I. US and UK cup letters match up to DD and then split.
What measurements are a 30I?
A snug underbust of about 30–31 in (76–79 cm) and a bust of about 39 in (98–100 cm). Measure with the tape level and use the calculator for an exact result.
Is 30I a big size?
30I has a very full cup volume for a 30 band. Cup letters only mean something next to the band: a 30I holds the same as 28J or 32H.