The Sister Size Web
Every size, bands 24–52 and cups A–K, colored by volume: sister sizes appear as diagonals, and tapping any cell lights its entire same-volume chain. The logic of the whole sizing system in one interactive map.
Tap any size
Grayed cells are combinations no maker cuts as standard; colored cells link to that size’s page. The sister calculator gives the one-size answer; this map gives the system.
Three things the picture proves
Diagonals are volumes. Constant color runs one-down-one-right: the system’s central trade, visible. Letters mean nothing alone. Follow any letter’s column top to bottom and watch its color (its volume) change class after class; “a D cup” spans the map’s whole spectrum, quantified on the volume page. The grid has edges, and they’re commercial. The gray corners aren’t bodies that don’t exist; they’re sizes nobody cuts: the boundary the extended-sizing guide walks.
The sister web: answered
What am I looking at?
The full bra-size grid with every cell colored by its volume class. Sizes sharing a color hold (approximately) the same cup volume on different bands: tap one and its entire sister chain lights up as a diagonal across the map.
Why do sister sizes form diagonals?
Because the system trades one band step against one cup letter: move right one band and down one letter and the volume stays put. On a band-by-cup grid, constant volume is therefore a diagonal line: the whole logic of sister sizing in one picture.
Are sister sizes really identical in volume?
Approximately: close enough that fitters use them as working equivalents, not so exact that wire width and band tension don't change. A sister swap keeps the volume and changes the frame; the sister calculator and each size's page carry the caveats.
Which chains are longest?
Mid-volume chains: a class that enters the grid at 28 and exits at 52 can have a dozen members. Chains shorten at the extremes: very small volumes exist only on small bands, very large only where deep cups are cut: which the map shows as diagonals clipped by the grid's edges.
Opens HauteFlair’s own hub page; use your measured size there. HauteFlair is owned by the same company as Brasize.ai; that relationship never changes the sizing math, charts, or fit advice on this page. How this site makes money.
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Two measurements, no inches added, sister sizes attached.
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