Apex Conversion

👙 Bra Size Converter

Convert full bra sizes — band and cup — between US, UK, EU, France, Australia, Japan, Russia, and South Korea. Handles US DDD = UK E, US G = UK F, and all other international cup differences.

Result

75C

34C US = 75C EU

Common Bra Size Conversions

InputUnitResultUnit
34United States (US)75European (EU)
34United States (US)90France (FR)
34United States (US)34United Kingdom (UK)
75European (EU)34United States (US)
36United States (US)14Australia / NZ (AU)
80European (EU)95France (FR)

Popular Conversions

Formula Reference

Band conversion reference:
  US/UK:  28   30   32   34   36   38   40   42   44
  EU:     60   65   70   75   80   85   90   95  100
  FR:     75   80   85   90   95  100  105  110  115
  AU:      6    8   10   12   14   16   18   20   22
  JP/RU/KR: same as EU

Cup conversion — canonical index (12 sizes, index 0–11):
  US:     AA  A   B   C   D   DD  DDD  G   H   I   J   K
  UK/AU/FR: AA  A   B   C   D   DD   E   F  FF   G  GG   H
  EU/JP/RU/KR: AA  A   B   C   D   E   F   G   H   I   J   K

Common mistakes:
  US DDD ≠ UK DDD — US DDD = UK E
  US G ≠ EU G — US G = EU G (index 7 matches here)
  US DD = UK DD (same), but US DD = EU E (different)

About Bra Size Conversions

A bra size has two parts: the band number (underbust circumference) and the cup letter (volume difference between full bust and underbust). Both change across international systems. Band numbers change because different countries measure in different units: the US and UK use even inches (28–44), most of Europe and Asia use centimeters rounded to multiples of five (60–100), France adds 15 to the EU band number, and Australia uses a garment-number scale (6–22).

Cup sizes appear identical for small sizes but diverge at the larger end. Below DD, every major system uses the same letters: A, B, C, D. From DD upward, three distinct conventions split: the US uses DD, DDD, G, H, I; the UK, AU, and FR use DD, E, F, FF, G, GG, H; and the EU, JP, RU, and KR use a continuous scale without double letters — D, E, F, G, H, I. This means a US 34DDD is a UK 34E and an EU 75F, not a UK 34DDD or EU 75DDD.

Why Cup Sizes Differ Internationally: The double-letter convention in the UK developed organically as the lingerie industry expanded into larger cup ranges. The US followed a different expansion path, reusing DDD where the UK introduced E. Continental Europe standardized on a clean alphabetic sequence without doubles. France adopted the UK-style double-letter cups but with the EU-style metric band. These independent developments left the world with three incompatible cup naming conventions above D, which this converter handles automatically for all supported systems.

Frequently Asked Questions

Why is US 34DDD not the same as UK 34DDD?

The US and UK cup systems diverge above D. The UK introduced E as the next step after DD, then F, FF, G, GG, H. The US instead reused DDD as the next step after DD, then jumped to G. This means US DDD = UK E, US G = UK F, US H = UK FF, and US I = UK G. If you wear a US DDD and are shopping a UK brand, look for UK size E — not UK DDD.

How does EU cup sizing differ from US and UK?

EU cups use a clean alphabetical sequence without double letters above D: the step after D is E, then F, G, H, I. The US uses DD and DDD where EU uses E and F. This means US DD = EU E, US DDD = EU F, US G = EU G. The EU system is used in Germany, Austria, the Netherlands, and most Scandinavian countries. JP, RU, and KR also follow this same cup sequence.

Is EU bra sizing the same as US sizing?

No — both band and cup differ. US 34C = EU 75C (band changes, C stays C). US 34DD = EU 75E (band changes, and cup changes from DD to E). US 34DDD = EU 75F. The EU band is a metric approximation of the underbust circumference rounded to the nearest 5 cm, while the US band is the underbust in even inches. EU cups follow a continuous A–K alphabet without double letters.

How do French bra sizes work?

French bra sizing adds 15 to the EU band number, so EU 75C = FR 90C and EU 80DD = FR 95DD. French cup letters follow the UK convention — DD, E, F, FF, G, GG, H — rather than the continuous EU sequence. When shopping French and Italian luxury brands, check whether sizes are labeled in EU or FR format, as both are common and easy to confuse.

What is the Australian bra size system?

Australian bra sizes use a garment-number band scale (6, 8, 10, 12, 14, 16, 18, 20, 22) that aligns with AU clothing sizes: AU 10 = US 32 = EU 70, AU 12 = US 34 = EU 75. Australian cup sizes follow the UK convention including DD, E, F, FF, G, GG, H — not the US DDD, G, H naming. A US 34DDD is an AU 12E.

Related Converters

Our Methodology

How we source and verify conversion factors.

Reference Library

Tables, charts, and authoritative reference data.

All Converters

All conversion results are provided for general informational purposes only. Our formulas use internationally recognized conversion factors; however, rounding may affect precision. Do not rely on these results for professional, medical, legal, or engineering decisions without independent verification. Read our full disclaimer.