EU to US Bra Size Converter
Estimate your bra size from underbust and bust measurements, or convert an existing size between US, UK, EU, FR and IT — plus its sister sizes.
Processed entirely in your browser — nothing you enter here is ever uploaded.
Result
About this tool
This page opens the bra size calculator preset for the EU-to-US direction: enter a European size such as 75B, and the matching US size appears at once, together with its two sister sizes.
EU band numbers measure underbust circumference in centimetres, rounded to the nearest 5, while US bands count in inches on a completely different scale — a EU 75 band converts to a US 34, not because of a simple offset but because the two scales use different units entirely. Cup letters mostly line up one-to-one through D, but the EU's plain A-to-L letter sequence has no doubled letters the way the US does above D, so an EU E becomes a US DD/E and an EU F becomes a US DDD/F. The calculator handles both conversions from real published band and cup tables.
This is the complete calculator, simply preconfigured for this pair — reverse the direction, pick UK, FR or IT instead, or switch to measuring a size from your own underbust and bust numbers. Everything runs locally in your browser, with nothing uploaded and no sign-up.
Example. An underbust of 30 in and a bust of 35 in produce the US size 34A, with sister sizes 32B and 36AA.
Limit. The cup index is clamped from AA through L, a bust that is not larger than the underbust is rejected, and convert mode accepts band numbers only from 20 to 60.