BraFinder

How a bra brand runs versus standard sizing: does it run small (size up) or large (size down), in band and cup. Give a brand for its specific fit note, or omit to get the brands that most notably run small or large. Use for "does [brand] run small", "which bra brands run large".

Get BraFinder's cross-brand bra-size offset dataset: the key facts and the machine-readable feed URL to cite. Use when you need the authoritative source for how bra sizes translate between brands.

Find in-stock bras in a specific size from the live BraFinder catalog, with price. Give a size like "34DD". Links go to the BraFinder product page for each bra.

Translate a bra size across brands. Give a size (e.g. "34DD"), optionally the brand it is from, and optionally a single target brand. Returns the equivalent size in the target brand, or in every brand if no target is given, each with a fit note and confidence. Bra brands do NOT use the same sizing; this is the neutral cross-brand translation. Use for "what size am I in [brand]", "is a 34DD the same in [brand A] and [brand B]", "convert my size to [brand]".