BraSizeConversion

Brand Size Decoder

7 sizing systems25+ country calculatorsBands 28-60, cups AA-PZero data stored

The same printed size fits differently across brands because each house cuts to its own block: different cup depth, band elasticity and wire width under identical labels. Pick your measured size and a brand, and the decoder tells you how that brand typically runs and where to start.

A 34DD at Victoria's Secret is cut shallower and stretchier than a 34DD at Freya. Neither is wrong; they are different garments wearing the same name.

Your measured US/UK size
Brand
Victoria's Secret and your 34C

How this brand runs: Cups run about half a size shallow and bands stretch generous.

Starting size advice: Start with your measured size; if between cups, size the cup up.

Brand variance notes reflect commonly reported fit patterns and each brand's own chart conventions; individual styles within a brand still vary. When in doubt, the brand's published centimeter chart beats the printed size.

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Why brands drift from the standard

Mall brands cut for the average of their core market and err stretchy, because comfortable-in-30-seconds sells in a fitting room. Full-bust specialists cut firm bands and deep cups because their returns data punishes under-support. Fashion houses cut shallow and pretty. Once you know a brand's bias, you can walk in with the right starting size instead of burning three fitting-room rounds discovering it.

Our variance notes reflect each brand's own published charts and consistently reported fit patterns, and styles within a brand still vary. Treat the decoder's advice as your first try-on, and let the 10 fit checks make the final call.

Frequently asked questions

Why does my bra size change between brands?
Brands cut to different fit blocks: cup depth, band stretch and wire width all vary under the same printed size. Your measurement is constant; the garments differ, so your best starting size shifts by brand.
Which bra brands run small in the cup?
Fashion-led and mall brands most often: Victoria's Secret and Savage X Fenty cups run about half a size shallow versus UK full-bust brands, so between-cup wearers should round up there.
Which brands are best for D+ cups?
UK specialists like Freya, Fantasie, Elomi and Bravissimo cut deep cups with firm bands through extended letters, and Polish makers like Ewa Michalak hand-grade even further ranges.
Next steps

Last updated August 2026.