Cherry SizeCalculator › All bra sizes, size by size › 30DD
30DD bra size — conversions, sister sizes & fit
A 30DD fits an underbust of about 63–67 cm with a bust 19–21 cm larger than the band. Here is everything that label actually means — and how to check it really fits you.
Your bra size
30DD US
Which measurements give 30DD?
| cm | |
|---|---|
| Underbust (snug) | 63–67 |
| Bust (fullest point) | 82–88 |
| Difference (cup volume) | 19–21 |
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 30DD
28DDD and 32D hold the same cup volume as 30DD with a tighter or looser band. If the band of a 30DD rides up, try 28DDD; if it digs in, try 32D.
A small underbust with a deep cup is the profile the high street serves worst: mainstream ranges often stop at D or DD on small bands. Specialist full-bust brands build exactly for this shape, with narrower wires and deeper cups that don't gape at the top. Resist sister-sizing up in the band to find stock — on a small frame, band support is everything. The projected shapes of full-bust lines will fit better than a stretched mainstream cup.
Who makes 30DD? 189 of the 632 brands in the Cherry Size catalogue are confirmed to carry 30DD 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 30DD brand by brand30DD in questions
What is 30DD in European sizing?
A 30DD corresponds to 65E in European sizing and 80E in French/Spanish sizing. The cup volume is identical — only the band numbering changes between systems.
Is 30DD big or small?
It is a full-bust size on a small frame — a combination mainstream brands often skip. Cup letters mean nothing alone: a cup only has a volume relative to its band, which is why 28DDD and 32D hold exactly the same volume as 30DD.
My 30DD doesn't fit — what should I try?
If the band rides up or feels loose, go to 28DDD. If the band digs in while the cup is fine, go to 32D. 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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