Last updated: July 2026
This tool is for general shopping guidance only. It is not medical advice, a diagnostic tool, or a substitute for a professional, in-person bra fitting.
Our calculator applies a standard band-and-cup formula to the two measurements you provide. It cannot account for breast shape, tissue density, asymmetry, or how a specific brand's pattern is cut — all of which affect real-world fit.
Sizing labelled 34B by one manufacturer, or in one country, can fit noticeably differently from a 34B made by another. Always check a brand's own size chart and, where possible, try before you buy.
If you have concerns about breast pain, rapid size change, asymmetry, or any other physical symptom, please consult a doctor. This site addresses clothing fit only and should not be used to assess health conditions.
By using this calculator you accept that Bra Size is not responsible for purchasing decisions, discomfort, returns, or any other outcome connected to relying on the result shown.
Reach us anytime through our contact page.