Parenting

A Handy Bra Size Calculator, Because We Know You Need It

by Hedy Phillips
Updated: 
Originally Published: 
Fruit in different bra sizes — bra size calculator.
Vaselena/Getty Images

Shopping for bras is practically an Olympic sport. Not only do sizes not seem to be universal, but actually knowing what size you need to begin with? Mystery! There’s a fairly reliable bra size calculator you can use to measure for bra size, but that doesn’t mean every bra that size will fit you. However, the knowledge is better than nothing, because at least if you know what measurements are right for you, a retail associate at a lingerie store will hopefully be able to help you translate that into the right bra. So with all that being said, let’s get into the nitty-gritty of how to measure your chest.

How to Measure Bra Size

First of all, a disclaimer: All bra measuring instructions are a little bit different, because most brands provide measuring instructions to fit their bras. Our instructions are fairly universal, but as always, adjust by brand where needed.

  • Step 1 — Find your band size: You’ll need a soft measuring tape to do the work. Your best bet is to measure your chest while braless, so nothing gets in the way. You’re first going to find your band size. Wrap the measuring tape around your chest, under your breasts, exactly where your bra band would sit. Don’t pull it too tight since you want this to sit how you’d want your bra band to sit. Make sure the measuring tape is parallel to the floor so that it’s accurate. In most brands (and historically speaking, when it comes to bra measuring), you add four to this number if it’s even, and add five to this number if it’s odd. In any case, round the number to the nearest whole number. Some brands advise you to measure this slightly differently. Victoria’s Secret wants you to measure around your chest at an angle. Wrap the measuring tape around your back at band level, but in the front, bring it up to where the straps would meet the cups. This number is the band size.
  • Step 2 — Find your bust size: This part is pretty straightforward and the same for most brands. Wrap your measuring tape around the fullest part of your breasts. Don’t pull it tight, and don’t leave it too loose. You want the measuring tape snug against you so that a bra will properly fit.

Step 3 — Put it together: Now take those two numbers to find cup size. Subtract the larger number (which should be the bust size) from the smaller number. The number you get will correspond with a letter for the cup size. If you get 0, your cup size is AA. If you get 1, your cup size is A, and so on and so forth. If your band number was 38 and your bust number was 34, the result is 4, which is a D cup. All together, that means your bra size would be 38D, because you measured your band as a 38.

This video should help you visualize exactly how to do this at home.

You also may wonder if bra sizes in swim tops are the same, and we are happy to tell you that generally speaking, yes, they are. Whatever bra size you wear should translate to a swimsuit, especially if you buy your swimsuit from the same retailer as your bras.

The most significant difference you’ll find in bra sizing is across stores. Whereas bra sizing does tend to be reasonably consistent, there’s always a chance that one brand will fit you slightly different than another. But just like you do with jeans, you’ll probably find a style and a brand that you love the most and continue to purchase consistently, saving yourself any hassle.

Bra Size Chart

Where you will find that bra sizes are not universal is from one country to another. Not only is your bra size different in another country because the United States uses inches and other countries use centimeters, but the cup size letters may be slightly different as well.

The U.S. and the U.K. have similar band sizes, but some European countries use centimeters for measurement, and some use a completely unique measurement. As you can see in the chart below from Brandable, both Italy and Australia have a unique sizing system, but if you’re shopping for bras in those countries, you can find your corresponding band size by following the chart.

The cup sizes are also a bit different, as you can see in this chart from Lingerie Addict.

Bra Sister Sizes

Guess what? Your bra sizes have sister sizes, too. These sizes are relative to your actual measurement, and this can come in handy if the store you’re shopping at doesn’t have your usual size or if you’re shopping for a slightly different style than usual. Sometimes a different style will fit you better in the sister size.

Sister sizing usually involves going down a size in the band while going up a size in the cup. As you can see in the graphic above, the sister sizing operates in that manner. If you usually wear a 38D, your closest sister size is a 36DD. You should opt for the closest sister size before going further down the line, because while they are sister sizes; they aren’t twin sister sizes. The closest sister should fit you the best.

All these tips are good rules of thumb and won’t translate to every brand or even to every country, but it’s better than not having any idea what you need when you walk into a store. Now go forth and upgrade your lingerie collection — you deserve it!

What to Do With Old Bras

Now that you know how to measure your breasts properly, you probably have a bunch of ill-fitting bras you want to get rid of. No worries! Here are a few ways you can recycle your old brassieres.

  • Give them away to a pal who has a larger or smaller (depending) cup size than you.
  • Use the bra straps to create headbands.
  • Cut out the padding and use them as shoe inserts.
  • Make a purse out of your old bras. Depending on your cup size, join the tiny purse craze or make yourself a medium-sized handbag. All sizes are fashionable (and beautiful).
  • Turn your bra into compost. This works if your bra is made from natural resources like cotton or wool. Remove everything that isn’t biodegradable, like tags or elastic.
  • Use your old bras for art!
  • Cut the bra cups out and sew them into a backless dress or swimsuit that needs more support.
  • There’s no such thing as too many bathing suit tops. So, if your bra straps break or have tears, cut them out. Then sew two wide pieces of silk to the top and side of each cup. That way, you can tie the top on like a halter. And if your sewing skills are exceptionally good, you can sew floral designs onto each cup.

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