About this site

BraSizeConversion is a free bra fit and sizing hub: calculators for every life stage, converters across 7 international systems, 25+ country-specific guides, a fit problem solver and the reference charts behind all of it. It exists because sizing is genuinely confusing, most advice online is a sales funnel, and the fix is honest math plus honest writing.

Everything runs in your browser. Measurements, sizes and quiz answers are processed on your device and never transmitted, stored or logged; there are no accounts and no email walls. The only thing we save locally is your cm/inches preference, on your own device.

Our method, stated plainly

We use the modern no-add method: your band is your actual snug underbust measurement rounded to sizing convention, and your cup letter is the bust-band difference at one inch per letter. The full cross-system rules are documented on the calculator's methodology section and every chart on the site uses identical math, so numbers agree wherever you meet them. Sizing conventions come from published brand charts and each system's standard practice; where real-world ranges exist, we say so instead of pretending precision.

Imagery policy

This site serves ages from first fittings to seniors, so all imagery is line-art and diagrams. No photographic body imagery appears anywhere, by design.

How the site earns

Advertising, and clearly marked Amazon affiliate links in product guides. As an Amazon Associate, this site earns from qualifying purchases. Recommendations are fit-first; the link follows the advice, never the other way. Corrections and suggestions are welcome through the contact page.