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