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