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