Bra Size Converter
US, UK, EU, FR, AU sizes.
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About Bra Size Converter
Convert a bra size between US, UK, EU, French and Australian systems. Pick the system you already know, choose your band and cup, and instantly see the matching band-and-cup in every other system.
Band sizes convert exactly (+2 inches = +5 cm), and cup letters are matched by the true bust-minus-band measurement so they stay consistent even above a D cup. It is completely free with no sign-up, and it runs entirely in your browser.
Frequently asked questions
- Is a US 34D the same as a UK 34D?
- Yes — up to and including a D cup the US and UK letters match. They only start to diverge above D, which is exactly where this converter keeps them aligned by measurement.
- Why do cup letters differ between countries above a D?
- Each system names larger cups differently: the US uses DD, DDD/F, G…, the UK uses DD, E, F, FF…, and the EU steps straight through D, E, F. This tool lines them up by the actual bust-minus-band measurement, so a US DDD/F becomes a UK E and an EU F. Charts vary a little for very large cups, so treat those as a close guide and check the brand's own size chart.
- How do EU and French band numbers work?
- The EU band is your under-bust in centimetres (a US 34 band is an EU 75), and the French band is the EU number plus 15 (so US 34 = EU 75 = FR 90).
- Are these conversions exact?
- Band sizes convert exactly. Cup fit still varies by brand and style, and many Asian brands run about a cup smaller, so when a label publishes its own size chart, trust that over any general converter.
- Does the tool store the sizes I enter?
- No. Everything runs in your browser and nothing you select is uploaded or saved.