Reviewed
42B bra size
A 42B has a 42-inch band and a B cup, about 2 inches between band and bust. In the UK it is 42B, in Australia 20B and in Europe 95B.
- US
- 42B
- UK
- 42B
- AU
- 20B
- EU
- 95B
- FR
- 110B
Also fits (sister sizes): 40C firmer band · 44A looser band · all same-volume sizes ↓
42B measurements
- Snug underbust
- 42–43 in · 107–109 cm
- Bust, fullest part
- about 44 in · 110–113 cm
- Cup difference
- 2 in (B 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.
42B sister sizes
Same cup volume, different band. If a 42B 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 42B doesn't fit
- Band rides up at the back
- Try 40C
- Band digs in, cups fit
- Try 44A
- Spilling over the cups
- Try 42C
- Cups gape or wrinkle
- Try 42A
Not sure what's wrong? Run through the 4-point fit check.
42B questions
What is the sister size of 42B?
40C (one band down, one cup up) and 44A (one band up, one cup down). Sister sizes hold the same cup volume on a different band.
What is 42B in UK, Australian and European sizes?
UK 42B, Australia 20B, Europe 95B and France 110B. US and UK cup letters match up to DD and then split.
What measurements are a 42B?
A snug underbust of about 42–43 in (107–109 cm) and a bust of about 44 in (110–113 cm). Measure with the tape level and use the calculator for an exact result.
Is 42B a big size?
42B has a very full cup volume for a 42 band. Cup letters only mean something next to the band: a 42B holds the same as 28I or 30H.