Cherry SizeCalculator › All bra sizes, size by size › 34B
34B bra size — conversions, sister sizes & fit
A 34B fits an underbust of about 73–77 cm with a bust 11–14 cm larger than the band. Here is everything that label actually means — and how to check it really fits you.
Your bra size
34B US
Which measurements give 34B?
| cm | |
|---|---|
| Underbust (snug) | 73–77 |
| Bust (fullest point) | 84–91 |
| Difference (cup volume) | 11–14 |
Between two sizes? Measurements near the edges of these ranges can also fit the neighbouring size — check the sister sizes below and, in doubt, trust the fit checks from our measuring guide.
Sister sizes of 34B
32C and 36A hold the same cup volume as 34B with a tighter or looser band. If the band of a 34B rides up, try 32C; if it digs in, try 36A.
This is one of the easiest profiles to shop: nearly every brand carries it. Your bigger risk is fit quality rather than availability — small cups on standard bands are often cut for a rounder shape than many bodies have, so gaping at the top edge is common. Balconette and demi cuts tend to follow a shallower curve better than full-coverage styles, and a band that stays put matters more than the cup label.
Who makes 34B? 406 of the 632 brands in the Cherry Size catalogue are confirmed to carry 34B in their standard range. But each of them cuts it differently — the app tells you the exact size to try at every one of them, from your own measurements.
See 34B brand by brand34B in questions
What is 34B in European sizing?
A 34B corresponds to 75B in European sizing and 90B in French/Spanish sizing. The cup volume is identical — only the band numbering changes between systems.
Is 34B big or small?
It is a common band with a shallower cup — widely stocked and easy to find. Cup letters mean nothing alone: a cup only has a volume relative to its band, which is why 32C and 36A hold exactly the same volume as 34B.
My 34B doesn't fit — what should I try?
If the band rides up or feels loose, go to 32C. If the band digs in while the cup is fine, go to 36A. If the cup overflows, try one cup up in the same band; if it wrinkles empty, one cup down. Two minutes with the calculator confirms it.
Nearby sizes
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