👙 Bra Size
40DDD Bra Size — UK, EU & French Conversion
A US 40DDD bra in UK, European and French sizing, with its sister sizes. Not sure 40DDD is right? Measure with the bra calculator first.
US 40DDD = UK 40E
EU 90F · French 105F
A US 40DDD bra converts to UK 40E, EU 90F and French 105F. The band number maps on a fixed scale, while cup letters shift between systems above D.
| Region | Size |
|---|---|
| US | 40DDD |
| UK | 40E |
| EU (Europe) | 90F |
| FR / ES (France, Spain) | 105F |
Sister sizes for 40DDD
Same cup volume, different band — try these if the band feels tight or loose but the cup is right:
38GSister down
42DDSister up
⚠️ US cup lettering above D varies by brand (DD vs E, DDD vs F). Match by the EU/UK equivalent when a brand's letters differ.
All bra sizes → · Bra calculator → · Converter →
What is a US 40DDD bra in UK and EU sizing?
A US 40DDD is a UK 40E, EU 90F and French 105F.
What are the sister sizes of 40DDD?
Same cup volume, different band: 38G, 42DD.
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