Cherry SizeCalculator › All bra sizes, size by size › 40C
40C bra size — conversions, sister sizes & fit
A 40C fits an underbust of about 88–92 cm with a bust 14–16 cm larger than the band. Here is everything that label actually means — and how to check it really fits you.
Your bra size
40C US
Which measurements give 40C?
| cm | |
|---|---|
| Underbust (snug) | 88–92 |
| Bust (fullest point) | 102–108 |
| Difference (cup volume) | 14–16 |
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 40C
38D and 42B hold the same cup volume as 40C with a tighter or looser band. If the band of a 40C rides up, try 38D; if it digs in, try 42B.
You are in the heart of every brand's range, which means maximum choice and also maximum inconsistency: this is where brands cut most aggressively different from one another. The same label can run a full cup apart between two houses. Lean on the fit checks — band level, wire flat against the sternum, no spill, no gap — rather than the label, and keep both sister sizes in mind at the fitting room.
Who makes 40C? 313 of the 632 brands in the Cherry Size catalogue are confirmed to carry 40C 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 40C brand by brand40C in questions
What is 40C in European sizing?
A 40C corresponds to 90C in European sizing and 105C in French/Spanish sizing. The cup volume is identical — only the band numbering changes between systems.
Is 40C big or small?
It sits right in the middle of the size range — the most commonly stocked profile. Cup letters mean nothing alone: a cup only has a volume relative to its band, which is why 38D and 42B hold exactly the same volume as 40C.
My 40C doesn't fit — what should I try?
If the band rides up or feels loose, go to 38D. If the band digs in while the cup is fine, go to 42B. 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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