Did you know that a UK DD cup is equivalent to an EU E cup, and in the US, it’s a DD/E?
For years, bra sizing has caused confusion—especially when comparing UK, European, and US sizes. One of the biggest misconceptions is around the UK DD and EU E cups. But where did this difference come from, and how has it shaped our perception of bra sizes?
Why is There a UK DD but an EU E?
Historically, many lingerie shops only stocked up to a D cup, with A, B, C, and D being the standard options. With a limited range of back sizes, many women had to squeeze into ill-fitting bras.
When the need for larger cup sizes became clear, British manufacturers hesitated to introduce an "E" cup, believing it sounded too big. Instead, they introduced "DD," thinking the double-lettering would make it seem more approachable. This marketing strategy stuck, and today, UK cup sizing continues with this pattern (E, F, FF, G, GG, etc.), while European brands use a simpler progression (D, E, F, G).
Myth: "DD is Just Half a Cup Bigger Than D"
Some believe that a DD cup is only half a step up from a D cup—but that’s a myth!
Myth: "All D cups are the same"
Cup sizes are relative to the band size, meaning a 32D and a 38D are vastly different in volume.
The Evolution of Bra Sizing & Body Positivity
Thankfully, the lingerie industry has evolved. DD+ sizes are now widely available, and brands are expanding their ranges to accommodate more body shapes. Women today are embracing their natural curves and understanding the importance of a well-fitting bra for comfort, support, and confidence.
At Naughty Knickers, we use UK sizing on our product pages and often include EU equivalents. However, many European brands print only the EU cup sizes on their tags, which can sometimes cause confusion.
To make things easier, we’ve included a size guide below, covering international cup and back size conversions, so you can find your perfect fit without compromising on style or comfort. If you ever need help with bra sizing, feel free to reach out - we're always happy to assist!
✨ P.S. A DD cup isn’t necessarily a large cup size - it all depends on the band size! But that’s a topic for another blog post. Stay tuned!
The below size guide shows the International conversions for CUP sizes.
| UK | EU | FR | US | AU |
| A | A | A | A | A |
| B | B | B | B | B |
| C | C | C | C | C |
| D | D | D | D | D |
| DD | E | E | DD/E | E |
| E | F | F | DDD/F | F |
| F | G | G | G | G |
| FF | H | H | H | H |
| G | J | J | I | J |
The below size guide shows the International conversions for BACK sizes.
| UK | EU | FR | US | AU |
| 30 | 65 | 80 | 30 | 8 |
| 32 | 70 | 85 | 32 | 10 |
| 34 | 75 | 90 | 34 | 12 |
| 36 | 80 | 95 | 36 | 14 |
| 38 | 85 | 100 | 38 | 16 |
| 40 | 90 | 105 | 40 | 18 |
