Convert bra sizes between EU, US, UK, FR and AU systems
You buy lingerie from a foreign store, receive a gift from the US, return something to a UK shop. Every time a different sizing system, different letters, different numbers. Is EU 75C the same as US 34C? Or completely different? And is UK 34DD actually US 34DD, or something else entirely?
This tool does the conversion for you. You enter the size you already know (say 75B in the European system) and you see the equivalent in all five systems at once: EU, US, UK, FR, AU. If you don't know your size, switch to "measure me" mode: you type two numbers (underbust and bust circumference) and the calculator figures out your size.
The most important trap, which nobody explains: after cup size D, the US and UK systems diverge. UK 34E is not US 34E, it's actually US 34DD. And US 34F is UK 34FF. This is where people get confused the most, so the tool shows it loud and clear on the screen, before you order a bra that won't fit.
How to use it
- Pick a mode at the top. If you already know your size, click "I have a size". If you don't know what to wear, click "Measure me".
- In "I have a size" mode: pick the system (EU, US, UK, FR or AU), then the band (e.g. 75) and cup (e.g. B).
- In "Measure me" mode: enter your underbust circumference (tape snug, right under the breasts) and bust circumference (tape loose, across the fullest part). The calculator picks the size for you.
- Below you get a conversion table with the equivalent in every system. Each row is the same size labelled differently per country.
- The red warning panel highlights the difference between US and UK after cup D. Read it before ordering a bra from another country, this is the single biggest mistake.
- Below the table is a neighbour size card: one cup and one band up and down. Useful if your standard size doesn't fit a particular brand.
When this is useful
Six situations where this tool gives you a concrete answer instead of guesswork:
- Ordering lingerie from an American store. You wear EU 75C, but the website only lists 34A, 34B, 34C... The calculator shows immediately: EU 75C = US 34C. You click and you know what to buy, no waiting for a return and shipping back and forth.
- Picking a gift for a partner. You've seen she wears cup B, you spotted a 75B label at home. In Europe that's obvious, but a London shop has 32A, 32B, 34A, 34B. The calculator translates: 75B (EU) = 34B (UK) = 34B (US). You buy with confidence.
- Buying on Vinted, eBay or another resale marketplace. The listing says "bra 36DD UK, like new". You check: UK 36DD = EU 80E = US 36DDD. You know it's not "too small", just a different system, and whether it actually fits you.
- Returning or exchanging a bra bought abroad. The seller asks "what size?". You look at the tag: 34F, but it's UK. The calculator translates: UK 34F = US 34DDD, so in a US shop you look for 34DDD or in a European shop for 75F.
- Helping someone close after weight change or surgery. The old size doesn't fit, you don't know what now. You type two measurements (underbust and bust) and the calculator shows the new size in every system at once, you can text a friend so she can buy in any country.
- Checking whether a "one size" offer makes sense. Some brands say "fits 32-36". You enter your size and see whether you're in that range or whether you should look for something tailored.