# breastcup sizes
**URL:** https://boards.straightdope.com/t/breastcup-sizes/290922
**Category:** Factual Questions
**Created:** [February 19, 2005, 6:55pm UTC](https://boards.straightdope.com/t/breastcup-sizes/290922 "2005-02-19T18:55:23Z")
**Posts on this page:** 20
**Page:** 1
### Author:  [@drhess](https://boards.straightdope.com/u/drhess)
#### Post date: [February 19, 2005, 6:55pm UTC](https://boards.straightdope.com/t/breastcup-sizes/290922/1 "2005-02-19T18:55:23Z")
Ok, being gay and male I don’t know anything about breast sizes. Ok, I guess some gay males might know more than I about bras, and ok, ok, some str8 guys would, too. Anyway, what does 34b mean? Is the number a measurement or just an index, like dress size 6.
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### Author:  [@Duckster](https://boards.straightdope.com/u/Duckster)
#### Post date: [February 19, 2005, 6:57pm UTC](https://boards.straightdope.com/t/breastcup-sizes/290922/2 "2005-02-19T18:57:21Z")
[Google](http://www.google.com/search?q=bra+cup+sizes&sourceid=mozilla&start=0&start=0&ie=utf-8&oe=utf-8)
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### Author:  [@Guinastasia](https://boards.straightdope.com/u/Guinastasia)
#### Post date: [February 19, 2005, 8:09pm UTC](https://boards.straightdope.com/t/breastcup-sizes/290922/3 "2005-02-19T20:09:26Z")
I don’t know how they came up with them in the first place, but the number measurement refers to the band that goes around a woman’s torso, while the letter is the actual breast itself.
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### Author:  [@dtilque](https://boards.straightdope.com/u/dtilque)
#### Post date: [February 19, 2005, 8:36pm UTC](https://boards.straightdope.com/t/breastcup-sizes/290922/4 "2005-02-19T20:36:22Z")
In the words of the Perfect Master [What’s the world’s largest commercially available bra size (revisited)?](http://www.straightdope.com/columns/000714.html)
> [@](#):
>
> For a good practical treatment of the sizing process, you can’t beat Victoria’s Secret, which gives the following explanation. First, one measures around the rib cage below the breasts and adds five to the result. This gives us the band size–the numerical part of 34C. Then one measures across the nipples. Even at Victoria’s Secret, no one ever says “nipples,” or “breasts” either, for that matter, giving the impression that women merely have an inexplicable expansion of the upper topography a la the Barbie doll. But we tell it like it is. The difference between the band size and the nipple measurement gives the cup size. Less than one inch is AA, one inch is A, two inches is B, and on up to five inches, DD. In short, for the breast-fixated, the focus ought to be the cup size, not the band.
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### Author:  [@drhess](https://boards.straightdope.com/u/drhess)
#### Post date: [February 23, 2005, 2:16pm UTC](https://boards.straightdope.com/t/breastcup-sizes/290922/5 "2005-02-23T14:16:16Z")
So, if a model says she is a 36c, that means her chest below the ribcage is 31 inches around and around the breasts she is 39 inches?
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### Author:  [@GilaB](https://boards.straightdope.com/u/GilaB)
#### Post date: [February 23, 2005, 5:35pm UTC](https://boards.straightdope.com/t/breastcup-sizes/290922/6 "2005-02-23T17:35:32Z")
Nope. (How would she walk? That sounds rather unweildy.) Her chest below the rib cage indeed measures around 31 inches, but the C means that it’s three inches more than the actual around-the-chest size, not the band number, ie 34 inches.
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### Author:  [@Ferret\_Herder](https://boards.straightdope.com/u/Ferret_Herder)
#### Post date: [February 23, 2005, 6:12pm UTC](https://boards.straightdope.com/t/breastcup-sizes/290922/7 "2005-02-23T18:12:03Z")
> [@GilaB](#):
>
> Nope. (How would she walk? That sounds rather unweildy.) Her chest below the rib cage indeed measures around 31 inches, but the C means that it’s three inches more than the actual around-the-chest size, not the band number, ie 34 inches.
But that’s not what the Straight Dope column quote says:
> [@](#):
>
> First, one measures around the rib cage below the breasts and adds five to the result. This gives us the band size–the numerical part of 34C. Then one measures across the nipples. […] **The difference between the band size and the nipple measurement gives the cup size.** Less than one inch is AA, one inch is A, two inches is B, and on up to five inches, DD. In short, for the breast-fixated, the focus ought to be the cup size, not the band.
So a 31" ribcage measurement, plus 5, equals the 36 band measurement. To get a C, you need a nipple-level measurement 3 inches greater than the band, making it 39 inches.
Remember, we’re talking about an overall circumference measurement here - an extra 8" is significant but not gigantic.
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### Author:  [@kimera](https://boards.straightdope.com/u/kimera)
#### Post date: [February 23, 2005, 6:43pm UTC](https://boards.straightdope.com/t/breastcup-sizes/290922/8 "2005-02-23T18:43:09Z")
> [@](#):
>
> According to this standard likely dating from the late 1930s to the early 1940s, you figure chest-band by measuring around your rib cage and adding five inches. You determine cup from the widest point around the bust (generally over the nipples), then add a letter for every inch difference between rib and bust circumference.
>
> …The A,B,C,D formula bears no actual relationship to real breast size—or volume, the crucial fit element. “It’s completely irrelevant,” says Tyrer. “It’s like measuring a motor car by the diameter of the gas cap.” And without accurate measure of breast volume, there is no way to define proper fit. “This is not rocket science,” he says. “It’s just straight-forward science, but nobody has done it.”
From [this](http://www.jessicaseigel.com/articles/bra.shtml) interesting article.
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### Author:  [@Max\_Torque](https://boards.straightdope.com/u/Max_Torque)
#### Post date: [February 23, 2005, 7:17pm UTC](https://boards.straightdope.com/t/breastcup-sizes/290922/9 "2005-02-23T19:17:23Z")
One question of mine remains unanswered: in parts of the world that don’t use our alphabet (like, say, China, Japan, or Russia), how do they designate the cup sizes?
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### Author:  [@treis](https://boards.straightdope.com/u/treis)
#### Post date: [February 23, 2005, 7:29pm UTC](https://boards.straightdope.com/t/breastcup-sizes/290922/10 "2005-02-23T19:29:16Z")
> [@Ferret Herder](#):
>
> But that’s not what the Straight Dope column quote says:
>
> So a 31" ribcage measurement, plus 5, equals the 36 band measurement. To get a C, you need a nipple-level measurement 3 inches greater than the band, making it 39 inches.
You say the ribcage is 31" then you add 5". What exactly is this measuring now?
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### Author:  [@Guinastasia](https://boards.straightdope.com/u/Guinastasia)
#### Post date: [February 23, 2005, 10:27pm UTC](https://boards.straightdope.com/t/breastcup-sizes/290922/11 "2005-02-23T22:27:24Z")
Well, I can’t speak for China or Japan, but Russia, and other countries that use the Cyrillic alphabet would probably just use the Cyrillic equivalent, since it’s the same letters, just different “symbols”, if you follow?
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### Author:  [@Kaitlyn](https://boards.straightdope.com/u/Kaitlyn)
#### Post date: [February 23, 2005, 10:35pm UTC](https://boards.straightdope.com/t/breastcup-sizes/290922/12 "2005-02-23T22:35:52Z")
> [@treis](#):
>
> You say the ribcage is 31" then you add 5". What exactly is this measuring now?
Adding 5 inches gets a measurement that is one inch smaller than an A cup, so that determining cup size can be done simply by matching letter to number A=1; B=2, and so forth. That’s easier to remember than a=6; b=7.
In a practical sense, measurements don’t always tell which size will give the best fit. A woman whose measurements indicate a 34C, if she’s a small C cup, might be more comfortable in a 36B, or vice versa. Like any other piece of clothing, but even more so than most, getting a bra that fits well is often a process of trial and error.
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### Author:  [@tadgoff](https://boards.straightdope.com/u/tadgoff)
#### Post date: [February 23, 2005, 10:59pm UTC](https://boards.straightdope.com/t/breastcup-sizes/290922/13 "2005-02-23T22:59:47Z")
> [@drhess](#):
>
> Ok, being gay and male I don’t know anything about breast sizes. Ok, I guess some gay males might know more than I about bras, and ok, ok, some str8 guys would, too. Anyway, what does 34b mean? Is the number a measurement or just an index, like dress size 6.
34 B means you have a flat chested sister.
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### Author:  [@Lamia](https://boards.straightdope.com/u/Lamia)
#### Post date: [February 23, 2005, 11:20pm UTC](https://boards.straightdope.com/t/breastcup-sizes/290922/14 "2005-02-23T23:20:56Z")
> [@drhess](#):
>
> So, if a model says she is a 36c, that means her chest below the ribcage is 31 inches around and around the breasts she is 39 inches?
More or less, although as **Kaitlyn** explains, there’s some variance between a woman’s genuine measurements and which bra will actually fit her best. And remember, the bra sizing system goes in two-inch increments (although some manufacturers do make in-between sizes), so plenty of women are going to be an inch off from their bra size.
Then, of course, the style and cut of the bra makes a lot of difference too…
This is why women take so long in the fitting room!
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### Author:  [@FilmGeek](https://boards.straightdope.com/u/FilmGeek)
#### Post date: [February 23, 2005, 11:44pm UTC](https://boards.straightdope.com/t/breastcup-sizes/290922/15 "2005-02-23T23:44:24Z")
An ill-fitting bra can lead to all sorts of problems, too. My shoulders can attest to that, if you care to interview them.
Another thing to note is that depending on the cut of the bra, you can go up a cup size and down a band size (or vice versa) and get the same fit.
For example. I’m a 40 DD. If I find a 42 D, that might fit, or a 38 E, or a 36 F, etc. This doesn’t work forever, (a 50 band size isn’t going to fit too well, no matter how small the cup is) but it does work within several sizes.
Bras are quite expensive for how long they last, so it’s important to find a good one and stick with it, especially if you’re large chested.
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### Author:  [@AwSnappity](https://boards.straightdope.com/u/AwSnappity)
#### Post date: [February 24, 2005, 12:20am UTC](https://boards.straightdope.com/t/breastcup-sizes/290922/16 "2005-02-24T00:20:16Z")
> [@tadgoff](#):
>
> 34 B means you have a flat chested sister.
Meh. I’m a 34B and my breasts are delightfully hand-sized.
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### Author:  [@ChoosyChipsAndCeilingWhacks](https://boards.straightdope.com/u/ChoosyChipsAndCeilingWhacks)
#### Post date: [February 24, 2005, 12:42am UTC](https://boards.straightdope.com/t/breastcup-sizes/290922/17 "2005-02-24T00:42:00Z")
38D-ish reporting in. Bra sizes are just as stupid as other women’s clothing sizes. I’ve always understood that the number was your rib cage measurement, the letter was equivalent to the numbef of inches “off” your breasts actually measured at the largest point.
However, like every other item of clothing, I have bras in 4 different sizes that fit me. Depends on the stretchiness of the materials, the style of the bra, etc. So stupid! I wish I could buy stuff without trying it on and know it would fit!
Anyway, I’m the same size no matter what the tag on my clothes says, so I usually don’t give this much thought.
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### Author:  [@Iceland\_Blue](https://boards.straightdope.com/u/Iceland_Blue)
#### Post date: [February 24, 2005, 12:43am UTC](https://boards.straightdope.com/t/breastcup-sizes/290922/18 "2005-02-24T00:43:35Z")
This thread needs pictures!! 😃
Be glad you’re not in Europe,where they measure in centimetres and you end up as a 85B or 90B 😃
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### Author:  [@Kaitlyn](https://boards.straightdope.com/u/Kaitlyn)
#### Post date: [February 24, 2005, 1:10am UTC](https://boards.straightdope.com/t/breastcup-sizes/290922/19 "2005-02-24T01:10:29Z")
> [@tadgoff](#):
>
> 34 B means you have a flat chested sister.
Bite your tongue. 34B is the one perfect size.
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### Author:  [@AwSnappity](https://boards.straightdope.com/u/AwSnappity)
#### Post date: [February 24, 2005, 1:17am UTC](https://boards.straightdope.com/t/breastcup-sizes/290922/20 "2005-02-24T01:17:51Z")
**Kaitlyn** : To celebrate us having the same bra size, I would totally suggest one of those jumping chest-bump things that men did (or maybe still do, but I think now it’s passé), but I’m a little sensitive right now.
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