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