US to UK conversion

38DD in UK Bra Size

Convert 38DD from US sizing to UK sizing, with the full international table, nearby sister sizes, and fit checks in one place.

Instant answer

38DD (US) =

38DD UK

In this sizing table, 38DD in US sizing converts to 38DD in UK sizing.

Sizing varies by brand

A conversion gives you the closest label in another sizing system, but brands can grade cups, wires, and bands differently. Use the converted size as a starting point, then check the retailer's chart and the fit of the actual bra.

Before you buy in UK sizing

Use 38DD as the translated label, not as a fit guarantee.
Check the retailer's size chart because some brands grade bands and cups differently.
If the cup volume feels close but the band changes, compare sister sizes before switching cup letters.
When possible, check return rules before buying across sizing systems.

Full conversion table for 38DD

38DD bra size conversion across US, UK, EU, French, and Australian sizing.
US	UK	EU	FR	AU
38DD	38DD	85E	100E	16DD

Bra sizing varies between brands. Use this as an accurate starting point and check the fit.

Sizes near 38DD in UK sizing

If 38DD is close but not right, these are the neighbouring US sizes and what each one becomes in UK sizing. Band neighbours change the fit around the ribcage; cup neighbours change volume.

US sizes adjacent to 38DD and their UK equivalents.
US size	UK size	How it differs
36DD	36DD	One band step snugger, same cup letter.
40DD	40DD	One band step looser, same cup letter.
38D	38D	One cup step down, same band.
38DDD	38E	One cup step up, same band.

What this conversion means

If you searched for 38dd in uk, the short answer is 38DD. The full table shows the same US size across every supported system so you can compare retailer charts without opening several pages.

Sister sizes for 38DD

Sister sizes: 36DDD and 40D can be worth checking when the cup volume feels close but the band needs a different feel.

What measurements make a 38DD?

The useful way to read 38DD is to separate the band from the cup step. In the current calculator formula, the closest starting range is about 37-39 inches (94-99 cm) under the bust and about 42.5-43.5 inches (108-110 cm) around the fullest part of the bust. The band comes from the underbust rounding, while the cup step comes from the difference between bust and band.

Is 38DD big or small?

Whether 38DD feels small, average, or full depends on the body and on the brand. In this size set, the US equivalent uses a fuller band and a fuller cup step. Cup letters are relative to the band, so a D on one band is not the same volume as a D on every other band. The most useful question is whether the band stays level and the cups hold smoothly, not whether the label sounds large or small.

If 38DD doesn't fit right

Band rides up: The band may be too loose or stretched out; try a snugger band or compare the snugger sister size.

Cups gape: The cup may be too roomy, too deep, or pulled away by a loose band; check the band before changing cup volume.

Cups spill: The cup volume may be too small or the cup shape may be too closed; try one cup step up before changing the band.

Straps dig in: The straps may be compensating for a band that is not supporting enough; reset the band fit before tightening straps.

How 38DD differs between brands

38DD can shift in feel from one retailer to another because brands grade bands and cups in their own way. A firmer elastic can make the same band feel smaller, and a shallow or narrow cup can make the same cup letter feel different. Check the retailer chart, read fit notes when available, and compare the label against the brand and region sizing guide before treating the conversion as final.

Shopping for 38DD

38DD is easiest to compare when you try shapes that show both cup volume and band tension clearly. If the cup is in a lower or middle step, lightly lined T-shirt styles can make gaps easy to spot. Fuller cup steps often benefit from styles with steadier side support, deeper cups, or a balconette shape depending on breast shape. For special outfits, compare the fit needs in the outfit guides before choosing a strapless, plunge, or backless option.

Bras in your size

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Everyday Fit Store

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Comfort Band Co.

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Soft Cup Edit

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FAQ

Is 38DD in the US the same as UK sizing?

Not exactly. 38DD is the US label, and this table converts it to 38DD in UK sizing, though some brands publish their own charts.

What is 38DD in European sizing?

In this same table, 38DD converts to 85E (EU). That helps when a retailer shows a European chart instead of a UK one.

How do I know if 38DD fits?

Check that the band stays level, the cups do not spill or gap, and the center gore sits close if the bra has wires. If the cup feels right but the band feels wrong, try a sister size.

What sister sizes work with 38DD?

36DDD and 40D are the closest sister-size options for 38DD in this dataset. Try a sister size when cup volume feels close but the band needs to feel snugger or looser.

Why do bra sizes differ between countries?

Countries and brands do not all use the same band labels or cup-letter sequence. A conversion translates the closest standard label, but the final fit still depends on the specific bra.

What measurements usually make 38DD?

The current calculator formula points to about 37-39 inches underbust and 42.5-43.5 inches bust, or roughly 94-99 cm and 108-110 cm. Treat that as a starting range and then check the real fit.