Bra Size Conversion – US, UK, EU, AU & JP
Enter your bra size in any system and we’ll show you the equivalent in US, UK, EU, AU, and Japanese sizing. Works for band and cup – fast, free, and private.
Bra Size Converter
Your size converted to all major systems.
Need to find your original size? Try the Bra Size Calculator or Sister Size Calculator.
Why Bra Sizes Differ Around the World
Bra sizes are not the same everywhere. The US, UK, EU, Australia, and Japan each have their own system. The band number and cup letter that fit you in one country might not be the same in another. That’s why you need a conversion tool – to make sure you get the right size when shopping internationally.
How the Conversion Works
Band Conversion
The band number is based on your underbust measurement in inches (US/UK) or centimeters (EU/JP). US and UK use the same band numbers. EU and JP use centimeters – for example, US 34 = EU 75.
Cup Conversion
Cup letters differ from D upwards. US DDD = UK E, US G = UK F, and so on. Our converter handles all the tricky mappings so you don’t have to guess.
Understanding Your Converted Size
- US – used in America and some online stores.
- UK – used in the UK, Australia, and many European brands. Band numbers same as US, but cup letters differ from DD up.
- EU – used in mainland Europe. Band numbers are in centimeters (e.g., 75).
- AU – follows UK sizing, but some brands use different band numbers (e.g., 12 instead of 34). Our converter uses the UK band for AU.
- JP – uses centimeters for band, similar to EU. Cup letters often follow US.
Common Conversion Mistakes
Many people think a US 34D is the same as a UK 34D – it is, for the band, but if you’re shopping for a US DDD, that’s a UK E. Always check the system of the brand you’re buying from. Our tool takes the guesswork out.
Got your size? Now find your sister sizes.
Try the Sister Size Calculator →Why Trust This Converter?
- Accurate – uses standard industry conversion charts.
- Free – no sign‑up, no charges.
- Private – all calculations run in your browser.
- Updated – we keep it in line with current brand sizing.
Remember: your converted size is a great guide, but always check the brand’s specific size chart – some brands fit differently.
Ready to convert your size?
Enter your size in the calculator above and see all the equivalents instantly.
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