Thread: How do you determine if a costume bra will fit?

After having bought (and then modified or sold) many costumes with the wrong bra fit (more difficult to find a good fit if one is larger than a D cup), I did some internet research to determine how I could better find costume bras that fit me.

And after buying and selling a few costumes on Bhuz, and also reading a few instances where cup sizing caused misunderstandings between buyers and sellers, I thought the information might help others who love to swap costumes.

SUMMARY
What I found was this important point: The volume of a cup size changes as the band size changes. As the band size increases, the cup size decreases. So a 34C is not the same cup size as a 36C. It is actually smaller. A 34C is the same cup size as a 36B and a 36C is the same cup size as a 34DD. The best representation I found was this picture. It was very enlightening to me!


(These are equivalent UK cup volumes.)


So it's really important that if a seller only says C cup and you are a C cup, that you clarify with band size, or better yet - measurements.

I'm a UK 32F, which by most (but not all) charts is equivalent to a US 32E. So if there is a post that says "D cup", why on earth would I look if it seems 2 cup sizes too small (besides the fact that I love beautiful costumes)? Although I can't wear a street bra with a larger band size (too loose), I can wear costume bras that fit 34DD and 36D.

That being said, I always ask for detailed measurements because " the results of a number of surveys and studies in many different countries show that between 70% to 100% of women wear incorrectly fitted bras."


After much experimentation, I've developed a formula that is now pretty accurate in determining whether a costume bra will fit me or not (and if you haven't surmised by all of this analysis, I'm an engineer ).



See references in next two posts for additional info that I found.


And if you have additional tips for bra sizing, please post!

Reference
Brassiere measurement - Wikipedia, the free encyclopedia

"The results of a number of surveys and studies in many different countries show that between 70% to 100% of women wear incorrectly fitted bras."

"One issue that complicates finding a correctly fitting bra is that band and cup sizes are not standardized, but vary considerably from one manufacturer to another, resulting in sizes that only provide an approximate fit. Women cannot rely on labeled bra sizes to identify a bra that fits properly"

"Manufacturers cut their bras differently, so, for example, two 34B bras from two companies won't fit the same woman"

"Most women assume that a B cup on a 34 band is the same size as a B cup on a 36 band. In fact, bra cup size is relative to the band size, as the actual volume of a cup size changes as the band size changes. The volume of a brassiere cup is the same for 30D, 32C, 34B, and 36A. These related bra sizes of the same cup volume are called sister sizes. It is sometimes possible that two adjacent sister sizes will both fit a woman, since the cup volume is the same, while the band size can be adjusted to a small degree by using the hook and eye fasteners in the bra clasp."

Reference
How Bras are Designed and Manufactured for the Proper Bra Fit by Tomima Edmark
"There are 2 important things to know about cup size.

The first is that a cup size on one band size is not equal to the same cup size on another band size. In other words, a 32D bra has smaller cup volume and diameter than a 34D bra yet both are a D cup. So I bet you're wondering why the industry assigns the same cup size to both.

Well, cup size is a measurement of how far your breasts project from your chest wall. Each cup size denotes a 1" increase in your body's circumference around your bust line. Knowing this fact can help you zero in on your correct bra size. For example, you try on a bra and the band feels comfortable, but your breasts are spilling out. Keep going up in cup sizes on the same band size until you find the bra that fits. Alternately, the cups fit great, but the band is too big. When you go down a band size, you now know that you need to go up a cup size to maintain the same underwire diameter and similar cup volume (Example: Go from a 40C to a 38D)."

"When a manufacturer grades his patterns to create different sizes for a bra style, he moves the bust points slightly wider with each cup size increase. B cup bust points are 1/2" farther apart than A cups. Bust points get 1/4" farther apart between B, C and D cups, and 1/8" farther apart with larger cup sizes."

Ah, but to complicate things further... Many costume manufacturers don't follow these rules! some have made up their own methods for cup sizing, so it is really important to ask the manufacturer's standards before buying a bra. It is generally much safer to just measure a bra which fits well and ask for measurements when buying. When making your own, beading can take the bras down a size or 2, so you may need to buy big as well.

*AND* it still might need adjustment, or might not work at all because not only do we all have different *sized* boobs, they are different shapes too, and positioned at different heights on the torso.

Birth and Baby -
Fun times!

So bottom line- yes, all the info you posted is *very helpful* for buying standard bras, but you also need to know what styles generally work for you costume wise. It is really nice to have help navigating all of this, but an awful lot of us rely on trial and error (after trial & error...)

SO envious of folks who can actually try on a variety of costumes before purchasing!

Oh I *completely* agree that this is not all that accurate when buying standard bras and it certainly doesn't replace getting detailed measurements!

What it does for me for costume bras is let me know that if the owner of the bra normally wears a 36D, the bra is in my ballpark (versus a 32D, which is 2 cup sizes difference and would not be family friendly ).

Then I follow up by asking for 7 detailed measurements as in my album: Bra Measurements pictures by Tatiana_MED - Photobucket and I plug them into my formula (which was developed by lots of costume trial and errors).

I've seen a couple of threads where a seller listed a C and the buyer was unhappy because it was a "really a B". But they were both probably right because the cup sizes were never referenced to the band size. This is the situation I'm hoping can be avoided by understanding that the band size also matters (and of course detailed measurements) :-)

completely, completely agree, and appreciate you posting it!

It really helps to have this info, but I wish folks would realize that *no matter what* there are probably going to have to be adjustments made. I just got a costume which only needed the straps shortened and I was in SHOCK, I tell you, because that just NEVER HAPPENS!

haha, rarely happens to me, too! Although lately the adjustments have become less due to my experience in judging what will fit, and my handy formula. I bought one costume recently where the band size was set to mine and the halter was the right length. AND the cups were perfect. And then my husband told me he didn't like the color on me

I'm still having troubles with some Bellas though. If I can find one with cups deep enough, they are often too wide at the top where the straps attach; and if I configure to a halter, they gape a bit. Shems posted a great fix for this that I'm going to attempt.