Good analogy. I wish more women (myself included, several years ago) knew this information. I was SO convinced that based on the dress size I wore I could never wear a smaller band size, but once I dropped down 2-4″ in band size and went 2-4 cup sizes up (depending on the brand and the style) I got SUCH a better fit and my bras lasted a LOT longer, too.

I always tell this to friends who ask me, to remember that the same cup size won’t look the same on different band sizes, since it doesn’t change proportionally, a B cup on a 28 band will look bigger than on a 40 band, because 2″ difference is more significant for 28″ than for 40″, although the 40B will be holding more “boob”

This also explains how is constant cup sizing is the problem with smaller band bras.
http://www.bratabase.com/blog/2009/jul/03/how-significant-is-an-inch-81/

Please email me and let me know what you think. I hope it’s OK I’m leaving a comment – I didn’t find an email address anywhere on the site. Thanks!

Bra sizes do vary based on the manufacturer, but not as much as clothing sizes (IMO), probably because there are more of them, and they’re more specific. I *do* think that some are better for women with more or less fat/muscle on the ribcage (you could be skin and bones and measure 34, or be a very smushy 34). And of course, some manufacturers are better for a certain shape of breast, or perkiness, or spacing between the breasts, etc.

But this 5″ thing? I don’t see how that would work for any manufacturer. Even Wacoal, which runs small in the band… I wear a 34, and might be able to wear a 36 on the tightest band, but not a 38 or 40. No way.

*Old lady bra fitters are usually the best, but this one was obnoxious.