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How to Measure the Right Bra Size

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How to find out exactly what size bra to buy.

How to find out exactly what size bra to buy.

Not Knowing Your Bra Size Is a Common Issue

An astonishing number of women don’t know their correct bra size.

I used to just buy bras that looked like they’d fit. You know, I'd look down at my chest, look up at a row of bras, and measure by eye. Then once, I managed to grab a store clerk’s attention. She measured me, and that day I returned home with two bras that wouldn’t have fit when I was 13.

In other words, your actual size may surprise you, especially if you've been buying the same size since you were 13. Here's precisely how to find out your exact bra size.

Measuring for a Bra

So how do you find the right bra size for your body? Well listen up, ladies, I’ve got some great chest-enhancing, body-fitting booby advice, and I’m sharing it with you because no one ever bothered to educate me on how to find the right bra. All you need is a body and a measuring tape.

If you’re a guy who wants a bra, please feel free to apply the following to your fantasy boobs. You’ll find no prejudice here.

How to Find Your Bra Size

Make sure you’re wearing a really lightweight bra while you're taking the measurement—nothing padded, just a plain one without embellishments. You definitely need a measuring tape to do this, because a ruler just won't do!

How to find your correct band size:

  1. Using a tailor's measuring tape, measure around your ribs right below your breasts. Don’t allow the tape to go slack and drop down—make sure the line is as straight and flat as possible, all the way around.
  2. Now write down this measurement, to the nearest inch. (If you measure 29¼" around, write 29".) Let's call this your exact rib measurement.
  3. Next, do some simple math to find out your band size. If the number is odd, add another five inches to it: This is your band size. If it's even, add four inches to find your band size. (For example, if you measure 31", add 5 for a band size of 36—or if you measure 28", then add 4: your band size is 32.)
  4. NOTE: If your exact rib measurement is 36 or larger, only add an extra 2 if odd, 1 if even. (For example, if you measure 37 inches, then add 2: Your band size is 39.)

How to find your correct bra cup size:

  1. While you're wearing an unpadded, lightweight bra, place the measuring tape around the fullest part of your breasts. Write down this number: it is your widest chest measurement.
  2. Next, simply subtract your band size from your widest chest measurement and check the chart below to find your corresponding letter cup size. For example, if your band size is 34 and your widest chest measurement is 37", then the difference is 3 inches and your cup size is a C. (Refer to the chart below for correct cup sizing.)

Bra Cup Size Chart

Measurement (widest chest measurement minus bandsize)Cup Size 

Less than 1 inch

AA Cup 

1 inch

A Cup 

2 inch

B Cup 

3 inch

C Cup 

4 inch 

D Cup 

5 inch 

DD Cup - E

6 inch

DDD Cup - F 

7 inch

DDDD Cup - G 

To find your band size, you'll need to first take your rib measurement: around your ribs, just under your breasts.

To find your band size, you'll need to first take your rib measurement: around your ribs, just under your breasts.

How to Buy the Right Bra

You know, wearing the right bra not only does wonders for your comfort (fits better, feels better, upholstered better), but it also makes you look slimmer. Great, huh? More bang for your buck. Besides, trying to squash a quart into a pint cup never works. One of the laws of physics: If it's too big, be prepared for spillage.

How You Know Your Bra Doesn't Fit:

  • the sausage back effect
  • underarm fat rolls
  • too many puppies in too small a basket

'Fess up ladies: who wears a badly fitting boulder-holder and spends all day scooping escaped bits of flesh back into a space that immediately ejects the excess... during that important meeting? And who hasn't performed the quick-and-snappy back-band shuffle? The shoulder-strap tweak? The under-wire scoop?


Tips for Always Getting a Bra That Fits

  1. If you can, try on at least a dozen bras. Even with the correct measurements in hand, you'll still need to make sure that the bra fits correctly.
  2. A lot of the support you get from any bra comes from the band, and that's why it's so important to make sure your band size is measured correctly!
  3. A correctly fitting bra will sit flat on your rib cage, and it should be centered. If it slides or bags away from you ribs, it's not going to support you. If you own any bras that don't hug your ribs anymore, toss them out.
  4. Re-measure yourself if you gain or lose weight. Makes sense to assume that if your waist has dropped or gained a size, so has your bust.
  5. Remember: Each time your band size increases or decreases, the cup size likely follows suit.
  6. It won't hurt to have yourself professionally fitted. If you have access to this service, use it.
  7. The straps should sit comfortably on your shoulders: no cutting in or dropping.
  8. The back band should sit slightly lower than the bra front. It should feel snug without feeling tight. If you've got muffins going on, it's too tight: Adjust it, and if that doesn't help the bra feel comfortable and snug, try another.

This content is accurate and true to the best of the author’s knowledge and is not meant to substitute for formal and individualized advice from a qualified professional.


Carrie on January 18, 2020:

I have the same problem as someone below. I measure 48 and I should add, but I'm in a 46 that is WAY too big as it is and have to move down. I'd like to know who came up with adding numbers. Something doesn't compute.

Dee on April 08, 2019:

This doesn’t work for heavy women. I have a difference of 4 1/2 inches but my breasts barely fit in a B cup. All my size is everywhere else other than my actual breasts.

Cheryl Dyal on February 16, 2019:

When I measure my bra size I come up with the band size being 48 then I add 4= 52.

My bust measured 55.5. So how do I determine my size when the bust is larger that the band? Am I missing something!

Cathy on December 12, 2017:

Serves you right. I'm glad to see this happening. Maybe then you can understand how us women feel being teased about our large breasts.

barry known as Carol on May 06, 2012:

thank you for the tip, I now have the right bra size and it is comfortable

Rismayanti from Tropical Island on April 20, 2010:

Great hub..helping, thanks

Andria (author) on April 02, 2010:

Cheeky Girl - I hope either something I've written or something left in the comments helps improve your ... you know ... boobs ;)

Cassandra Mantis from UK and Nerujenia on March 31, 2010:

I am so glad I saw this! I will book mark this one for sure! Whehey! Thank you! About time someone did this on hubs!! : )

Andria (author) on March 31, 2010:

Dim - I'm saving the world ... one chest at a time ;)

Andria (author) on March 31, 2010:

Mist1302 - I used the universal method but for sure one size doesn't fit all. That's for another method for measuring you cra size correctly :)

Justine - glad you may have found another way to upholster your boobs!

Andria (author) on March 31, 2010:

suiiki - thanks for the alternative advice :) I think it's helpful to leave different methods. The above pretty much works for me but I'm not everyone else!

Paradise - just don't bother with my original method ;)

Candie - that's what jiggling boobies in too small a bra always look like lol :)

Dim Flaxenwick from Great Britain on March 31, 2010:

That gave me a good chuckle, thank you. I've made just about every mistake mentioned here.I have also just measured and 'yes' I need a different size.

Why am I not surprised? I'm constantly uncomfortable in my bras. Thanks for the advice. Great stuff!!

Justine76 on March 31, 2010:

HAHAHAH!! FD, I am actually going shopping for new clothes soon. We had a bon fire for my birthday a while ago, and I ripped my only pair of jeans. I am hopefully going to spend some money on new undergarments as well. They really make a difference on how well your clothes fit, but Ill need to find someone with a camera to tag along... :)

HEY I just noticed some comments to help me, thanks guys!

Mist1302 on March 30, 2010:

For those girls with larger cups, it can be fairly impossible to find anything in a regular store. (And yes, 'anomalies' like 32F happen - to real women. Wearing the correct band and cup will make you feel better and look better - but unless you are lucky enough to live in the UK, it is necessary to find a specialty store or buy online.)

But the way you measure band is incorrect. When taking the underbust measurement, add only 2-3 inches to find band size. It quite honestly depends how squishy you are around the ribs and what size actually fits, for the same measurement seems to vary woman to woman. I measure about 28.5 inches underbust, and I wear either a 30 or 32 band depending on brand. (That's another factor in correct size.)

I hope this helps.

Candie V from Whereever there's wolves!! And Bikers!! Cummon Flash, We need an adventure! on March 29, 2010:

LOLOL!! "Too many puppies in too small a basket"!!! You crack me up!. I had a girl friend (full figured to be sure) that used to laugh and say she had to by bras in the hat department! Thanks FD!

Paradise7 from Upstate New York on March 29, 2010:

Thanks, I'm bookmarking this for the next time I go bra-shopping. I've bought bras online using the size charts and doing the measuring with a LOT more success than I've had buying bras in the store (note for Justine!).

Suiiki from City of the Newly Wed and Nearly Dead on March 28, 2010:

I was always taught that to find your cup size, you need to find how much bigger your boobs are than your band size (before adding to find the actual band size) For instance, my breasts are 5 inches larger than my measurement just under the bust, making me a DD cup.

I could be wrong, but that's the way my mum taught me and her mum (A dressmaker) taught her...

It always worked for me (And could help Justine76)

Andria (author) on March 28, 2010:

drbj - I don't think it's a first. I just wrote it on the hop. So to speak ;) And the joke made me laugh ... gravity is very cruel to women. And men ...

Ethel - The part about me measuring by hand is true. 'Twas in a store in my local town. I semi-cured me. I got all fascinated one time with those gel filled bras. I ended up buying another useless bra that day too ;)

Ethel Smith from Kingston-Upon-Hull on March 28, 2010:

You managed to get a good amount of humour into this Hub. Not easy with the subject in hand

drbj and sherry from south Florida on March 27, 2010:

A hub on how to measure your bra size? I haven't checked but this must be the first hub of its kind.

I wish that the comments section could show an image but since it doesn't, I'll describe a funny cartoon I just saw that fits (joke) right here.

Picture an elderly couple sitting side by side on a sofa. He puts his hand under her blouse to fondle her breast and she says, "No, Henry, they're not up there any more!"

Oh, well, you had to BE there.

Andria (author) on March 27, 2010:

Lol Justine that's a crime, surely?! I don't know - go try one on and see. And of course I'll need pictures for evidence ;)

Justine76 on March 27, 2010:

HAHAHHAHAH!! Ive had this problem for so long. Yes, just under the bustline 27 inces. (skip the math for the band size, Ive got 7 inches of boob? that's NOT going to fit in a B cup!!) It may be the fact that where I live doesn't offer much for variety, bras are kinda like jeans, different brands will vary in their sizes somewhat.

Andria (author) on March 27, 2010:

lol Justine all I can say is the above is the standardized method for finding your bra size. If it says you're a 32B ... and you're not then something's wrong. You're definitely taking the first measurement from just under your bustline right? Adding the right amount to find the band/bra size? You'll have to get your boobies out lol, so I can see. And don't worry - I won't share ;)

Justine76 on March 27, 2010:

haha. sausages. :) Here is my big issue. I get 27 inches for the first measurement. so..add 5, right? 32. Now, next measurement, 34. So I should be a 32B? not a chance will that fit. Ive tried!! what am I doing wrong? And the shopping? Your so right! He wont mind a bit!!