Cherry SizeCalculator › All bra sizes, size by size › 38B
38B bra size — conversions, sister sizes & fit
A 38B fits an underbust of about 83–87 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
38B US
Which measurements give 38B?
| cm | |
|---|---|
| Underbust (snug) | 83–87 |
| Bust (fullest point) | 94–101 |
| 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 38B
36C and 40A hold the same cup volume as 38B with a tighter or looser band. If the band of a 38B rides up, try 36C; if it digs in, try 40A.
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 38B? 387 of the 632 brands in the Cherry Size catalogue are confirmed to carry 38B 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 38B brand by brand38B in questions
What is 38B in European sizing?
A 38B corresponds to 85B in European sizing and 100B in French/Spanish sizing. The cup volume is identical — only the band numbering changes between systems.
Is 38B 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 36C and 40A hold exactly the same volume as 38B.
My 38B doesn't fit — what should I try?
If the band rides up or feels loose, go to 36C. If the band digs in while the cup is fine, go to 40A. 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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