Bra size conversion: US, UK, EU, French and Australian
Compare international bra size labels without assuming that every brand uses the same cup sequence or fit.
How to convert a bra size
Start with a size that fits you and identify its sizing system. Match the band label and the cup sequence separately. A label conversion translates a starting size; it does not calculate a new size from your body measurements.
Check the exact manufacturer’s international chart before buying. Some US brands use DDD, F or other labels differently, and EU cup grading may differ from the general label progression shown here.
Bra size conversion chart: a 34-band example
These illustrative rows follow the calculator’s approximate label model. US/UK band 34 corresponds to EU 75, French 90 and Australian 12 in this model. This is a label mapping, not a conversion of inches into centimetres or a promise of equal physical fit.
| US | UK | EU | France | Australia |
|---|---|---|---|---|
| 34A | 34A | 75A | 90A | 12A |
| 34B | 34B | 75B | 90B | 12B |
| 34C | 34C | 75C | 90C | 12C |
| 34D | 34D | 75D | 90D | 12D |
| 34DD | 34DD | 75E | 90E | 12DD |
| 34DDD | 34E | 75F | 90F | 12E |
| 34G | 34F | 75G | 90G | 12F |
| 34H | 34FF | 75H | 90H | 12FF |
Why US and UK cup letters differ
The example progression agrees through D and DD in US and UK labels. After that, this model maps US DDD to UK E, US G to UK F, and US H to UK FF. UK sequences include double letters such as FF and GG; the general US sequence used here does not.
Never assume a US G and a UK G are the same. A brand-specific chart can differ from this general table, particularly when a brand uses F instead of DDD or its own cup progression.
European, French and Australian band numbers
In this model, US/UK bands 32, 34 and 36 map to EU 70, 75 and 80; French 85, 90 and 95; and Australian 10, 12 and 14. EU and French labels are not interchangeable: their numbers differ even when the illustrative cup label is the same.
A garment’s band label is not necessarily your measured underbust. Manufacturers may use rounding, offsets or measurement buckets. Switching the calculator from inches to centimetres changes measurement units, not the meaning of the garment’s size label.
Conversion versus sister sizing
A conversion expresses a starting size in another system. Sister sizing changes the band and cup together within a system to suggest approximately similar cup volume. They answer different questions.
For a new measurement-based starting point, use the calculator and measurement guide. For a band that feels too loose or too tight, read the sister-size guide and assess the cups before changing the band.
What if the brand does not have my size?
A label in this guide does not establish that a particular brand sells it. Check the official chart, the style’s available sizes and its return policy. Do not treat a blank chart cell or an unreviewed brand as a verified recommendation.