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