Reference
The Bra Fitting Encyclopedia
Everything we know about bras and fit, fact-checked and organized by question. Each page answers its question in the first paragraph, then shows the work.
How to Measure Your Bra Size at HomeSix measurements, three underbust and three bust, averaged. Band is the nearest even number; cup is bust minus band. Or skip the tape: the Radical scan measures you from two photos.
How Bra Sizing WorksBand plus cup, and why there is no fixed D cup: cup size is a ratio proportional to band size. Also the +4 vs +0 method split that explains old and new sizes.
Bra Size ChartsUS and UK cup charts, the full sister-size table, and a fit-adjustment table keyed to the most common fit problems.
How to Tell If Your Bra FitsCheck band first, then cups, then straps, with the specific signs that say go up or go down in each.
How to Put On a BraLoose straps, loosest hook, scoop and swoop, underwires at the breast root, straps last. The order is the whole trick.
The Parts of a BraBand, cups, gore, straps, underwire, hooks and eyes, channeling, and what each part is supposed to do.
Breast Shape and FitProjection, fullness distribution, and root width explain why the same size fits differently in different bras.
Between SizesWhat to do when measurements don't line up: ribcage compressibility, small vs large bands, and where sizing methods disagree.
What this encyclopedia is. A purely educational reference: how bras work, how to measure, how sizing functions, and how to assess fit. It does not cover brand recommendations, specific styles, shopping guidance, or medical questions. The methods here are educational guidelines, not universal rules; sizing varies across brands, countries, and bodies. Always prioritize comfort and personal fit over any calculated size, and consult a healthcare professional with medical questions about your breasts. The full reference is also available as a single Markdown file.
Want the fit without the arithmetic?
The Radical scan replaces all of this measuring with two photos, front and side, taken on your phone at home. Our scan partner Bodygram reads them into your measurements and a 3D model of your body, then your pattern is drafted from your measurements and your answers, the same questions a certified fitter asks in person.
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