Reviewed
34B bra size
A 34B has a 34-inch band and a B cup, about 2 inches between band and bust. In the UK it is 34B, in Australia 12B and in Europe 75B.
- US
- 34B
- UK
- 34B
- AU
- 12B
- EU
- 75B
- FR
- 90B
Also fits (sister sizes): 32C firmer band · 36A looser band · all same-volume sizes ↓
34B measurements
- Snug underbust
- 34–35 in · 86–89 cm
- Bust, fullest part
- about 36 in · 90–93 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.
34B sister sizes
Same cup volume, different band. If a 34B 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 34B doesn't fit
- Band rides up at the back
- Try 32C
- Band digs in, cups fit
- Try 36A
- Spilling over the cups
- Try 34C
- Cups gape or wrinkle
- Try 34A
Not sure what's wrong? Run through the 4-point fit check.
Compare 34B
Sizes next to 34B
34B questions
What is the sister size of 34B?
32C (one band down, one cup up) and 36A (one band up, one cup down). Sister sizes hold the same cup volume on a different band.
What is 34B in UK, Australian and European sizes?
UK 34B, Australia 12B, Europe 75B and France 90B. US and UK cup letters match up to DD and then split.
What measurements are a 34B?
A snug underbust of about 34–35 in (86–89 cm) and a bust of about 36 in (90–93 cm). Measure with the tape level and use the calculator for an exact result.
Is 34B a big size?
34B has a mid-range cup volume for a 34 band. Cup letters only mean something next to the band: a 34B holds the same as 28DD or 30D.