How to Measure Your Bra Size

Four Methods:Sizing BasicsModern SizingChecking for FitTraditional Sizing

Believe it or not, at least 80% of women wear an incorrectly sized bra! Most people wear a bra too large in the back and too small in the cups. Although sizing can vary slightly between brands, all follow a basic measurement system that you can use to measure your bra size in the comfort of your own home.

Method 1
Sizing Basics

  1. Image titled Measure Your Bra Size Step 1
    Know that cup size is not absolute. This is the biggest myth about bra sizes: that a D cup looks the same on every band size, or that having small breasts automatically means you're an A cup. Actually, cup size is proportional to band size — meaning it's dependent on your band measurement. For instance, a 32 D will fill out less volume than a 36 D, but they're both D cups.
  2. Image titled Measure Your Bra Size Step 2
    Understand how a correctly fitted bra should look and feel. There are a few tell-tale signs that indicate whether or not a bra fits you. Here's what to keep an eye out for as you're measuring yourself and trying on different sizes:
    • A snug band: The band is what should do the majority of the work supporting your breasts, not the straps. You should be able to put one or two fingers under the band, but no more.
    • Sufficient side coverage: You shouldn't have any tissue coming out from the sides of the cups, beneath your armpits. On an underwire bra, you can assess side coverage with the underwire: if the end of it is pointing toward the middle of your armpit, you're good to go.
    • A flat gore: The gore (the part of the bra band that's between the cups) should sit flat against your chest, without digging into your skin uncomfortably. If it doesn't, you're wearing the wrong bra.
    • A smooth curve: Avoid the dreaded "quad-boob" that results from the top of a too-small cup cutting into breast tissue above the bra. Instead, look for a fit that results in a clean silhouette with no stray tissue.
  3. Image titled Measure Your Bra Size Step 3
    Be aware of different breast shapes. So what happens if you find a bra in your size, but it still fits wrong? You're probably not picking the right bra cut for your breast shape. Try these solutions to common shape issues:
    • Shallow breasts: If your breast tissue is evenly spread over a wider area, with less projection, you probably have a shallow shape. (Another tell-tale sign: having breast tissue near your collarbones despite being relatively small-busted.) Shallow breasts fit best in balconette or demi-cup bras, with a cup that's open on top and cut horizontally. Avoid plunge styles.
    • Pendulous or tuberous breasts: If the base of your breast is relatively narrow, but the actual tissue hangs down quite a bit, don't despair! Instead, look for bras that have underwires, well-separated cups and fuller breast coverage. Avoid demi cups and plunge bras.
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    Know about sister sizes. If you find a bra that's close to a perfect fit but not quite there, try a sister size. It might provide just enough variation to correct the slight differences between manufacturers.
    • Go down a sister size: Reduce your band size by two, but take your cup size up one interval. For instance, you might go from a 36 C to a 34 D.
    • Go up a sister size: Increase your band size by two, but go down one cup size. For instance, you might go from a 36 C to a 38 B.
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    Navigate different fitting styles. Currently, there are two different bra fitting styles (outlined below). The modern measurement is being adopted by more manufacturers, though some still use the traditional style. Unfortunately, it's difficult to know which system individual designers and labels use. Here's how to hedge your bets:
    • If you're trying on bras in a store, it's a good idea to know what your size is for both styles.
    • If you're ordering online, try to find a site that has a flexible return policy.
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    Be wary of professional fittings. Asking for a seasoned professional to measure you is a great idea if you're starting from square one — she'll probably be able to suggest cuts and styles that could work for you. However, being fitted comes with a few caveats:
    • Avoid stores that carry a limited range. A fitter at one of these shops might try to incorrectly sell you a size that they have on-hand, instead of your true size. Before you commit to a fitting, make sure the store carries smaller band sizes (such as 28 and 30) and larger cups (DDD and up). Good choices in the US include department stores like Nordstrom and Dillard's.
    • Ask to be fitted with both measurement systems. That way, you have an idea of what size to try if one style produces a completely wrong fit.
    • Don't leave your current bra on. If your fitter tries to measure you with your bra still on, it's probably not going to be the correct measurement. If you're concerned about modesty, wear a thin but close-fitting tank top to your fitting, and simply remove the bra underneath.

Method 2
Modern Sizing

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    Measure your band size. This is the easiest part of the process — your band size should be fairly stable and straightforward.
    • Run a tape measure all the way around your body just underneath your breasts and take a measurement in inches. Make sure the tape measure is horizontal and fairly snug. Your arms should be down. Write down this number.
    • If this measurement is an odd number, then you should try out bras in both the size below your measurement and the size above. [1] For example, if you measured 31 inches (78.7cm), your band size could be 30 or 32.
    • If your measurement is already an even number, this is almost always your band size, but you may need a smaller or larger size depending on your body type.
  2. Image titled Measure Your Bra Size Step 8
    Determine your cup size. Remember, your cup size isn't an absolute measure — it's in proportion to your band size.
    • Bend over so that your chest is parallel to the ground. This is so that you'll be measuring all of your breast tissue — not just what protrudes outward when you're standing up.
    • Measure around your torso, so that the tape is over the fullest part of your breasts. Don't pull the tape too tightly — it should be tight enough that it doesn't evenly move, but not so tight that's pressing into your breast tissue. Write down the number.
    • Make sure your tape measure is level to the ground. It shouldn't be a few inches down your back, or you'll end up with an uneven measurement. To combat this, try to measure yourself in front of a mirror, or ask your partner or close friend to help you.
    • Calculate your cup size. To do this, you'll subtract your band measurement from the cup measurement you just took. The difference between the two numbers determines your cup size:
      • Less than 1 inch (2.5 cm) = AA
      • 1 inch (2.5 cm) = A
      • 2 inches (5 cm) = B
      • 3 inches (7.5 cm) = C
      • 4 inches (10 cm) = D
      • 5 inches (12.5 cm) = DD
      • 6 inches (15 cm) = DDD (E in UK sizing)
      • 7 inches (18 cm) = DDDD/F (F in UK sizing)
      • 8 inches (20.5 cm) = G/H (FF in UK sizing)
      • 9 inches (23 cm) = I/J (G in UK sizing)
      • 10 inches (25.5 cm) = J (GG in UK sizing)
      • The majority of leading brands use UK cup sizing: AA, A, B, C, D, DD, E, F, FF, G, GG, H, HH, J, JJ, K, KK, L, LL. If you're shopping in the US you might see cup sizes such as DDD or DDDD. These are equivalent to E and F. If you're in any doubt, particularly with larger cup sizes, you can refer to an international bra sizing chart.[2]

Method 3
Checking for Fit

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    Try on a bra with the band and cup size you've arrived at in these steps. You should not regard this as your definitive size until you have tried on a few bras, and even then you will often find you need a different size in different brands or styles of bra.
  2. Image titled Measure Your Bra Size Step 12
    Put on the bra on correctly. Known as the "scoop and swoop," this is a more correct way to make sure all of your breast tissue is in the bra:
    • After taking the bra off its hanger the shoulder straps will need to be lengthened. Put your arms through them and lean forward slightly so that your bust falls into the cups.
    • Fasten the bra on the largest set of hooks and eyes. Don't worry if it's tricky to fasten, if you're trying a smaller back size you will notice that you need to stretch it around you to make the hooks and eyes meet.
    • Still leaning forward, take hold of the underwires and give them a wiggle from side to side to make sure you're settled comfortably into the cups.
    • For each side in turn, slip your hand into the side of the cup and lift each breast towards the centre.
    • You will probably have to adjust the length of the shoulder straps. Slip them off your shoulders and adjust the sliders so that the straps are short enough to stay in place but don't cut in.
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    Check the band size. The correct band size is the smallest you can comfortably wear. (This might be smaller than your underbust measurement-bra bands are quite stretchy, especially at 42+.)[3] It needs to be firm enough that the bra is still fairly supportive without weighing down heavily on the shoulder straps.
    • You should be able to run your fingers around the inside of the band, but not much more. A good rule of thumb is that you should be able to fit no more than a fist under the back of the bra where your spine is at.
    • It should fit on the biggest adjustment, but will probably be too tight if you try to fasten it on the smallest size. Bras are designed to fit like this so that you can tighten the band as the elastic starts to wear out.
    • If the band is roomy enough for you to be able to comfortably fasten it on the tightest adjustment, try a smaller band, for example if a 32D is too loose, try a 30DD. Remember that the cup size has to be changed when you move to a different band size - for every band you go down, you must go up by one cup size in order for the cups to remain the same capacity and vice versa.
    • If you find the band painfully tight you should try going up a cup size because too small of cups can make a band which is too big or the right size seem ill fitting. If going up a size, maybe even several does not work, then try going a band up and a cup down, e.g. 28G to 30FF. However, try the first method before the latter.
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    Check the cup size. The correct cup size should be completely filled out with no wrinkling of the fabric or space in the cups, but any spillage or "double boob" means the cup size is too small, even in low cut or pushup bras.
    • Check around the cups for any bulging, not only at the front but also at the sides under your arms.
    • Make sure the underwire encloses your whole breast and lies flat against your rib cage.
    • Check at the sides under your arms to make sure the underwires are sitting on your ribs, not on soft breast tissue. If they're cutting into the sides of your breasts then you need a larger cup size. Also be aware that if you have been wearing a bra with a too big band and too small cups, you may have ended up with migrated tissue, which will seem to be armpit rolls, or back rolls. This can be fixed after getting a well fitting bra.
    • If the underwires are pressing painfully against your breastbone at the centre front you may need a smaller cup size or you could try a plunge style with a lower centre front (this is more likely to be an issue with the cups than the band.) Or you might just be human, and it's the shaping of your ribcage. In that case, wait for the bra to be "broken in" and see how it fits then, or go with the lower centre front.
    • If you think the cups might be too small but you're not sure, try on a bigger cup size as well to double check. It will usually be obvious if the smaller size fits better.
  5. Image titled Measure Your Bra Size Step 15
    See how it looks with your top on. You've found a new bra that fits well, maybe in a different size or style to the ones you're used to. Now it's time to see what it does for your figure! If you're trying a t-shirt bra it's also important to make sure it gives you a smooth line under fitted clothes.
    • If you look side on to the mirror, you should be able to see that your bust is approximately halfway between your elbow and your shoulder.
    • In a well fitting bra, your bustline will be supported at the right level. A lot of people find that their clothes fit a lot better, and they discover a waist that could never be seen before! If your bustline had previously been quite low because of a poorly supporting bra, you may even find that you need to wear a smaller dress size.
    • A fitted t-shirt will show up any bulges from cups which are too small, and likewise a moulded bra that is not filled out will show lines at the bust where the edge of the cups are visible. It's also useful to make sure that the colour of your bra is not showing through a thin or light coloured top - if you need to make your bra invisible, go for seamless cups which match your own skin colour rather than the colour of your top.
    • It is a common concern that wearing a smaller band size will make a big bulge around your back. However, these bulges are actually caused by the back of the bra riding up when it is too large. You should find that when the band sits lower at the back, it fits firmly and remains horizontal, rather than pushing upwards creating a bulge.

Method 4
Traditional Sizing

  1. Image titled Measure Your Bra Size Step 9
    Measure your band size. Wrap a tape measure around your ribcage, just beneath where your breast tissue ends. Then:
    • If the measurement is even: Add 4 inches (10 centimeters).
    • If the measurement is odd: Add 5 inches (12.5 centimeters).
    • Be aware that most brands no longer use this band measurement system. The "add four" method was popularized by Warners in the 1930s when bra design was in its infancy and it simply doesn't work with modern bras.[4] Still, it's good to be aware that it's out there.
  2. Image titled Measure Your Bra Size Step 10
    Measure your cup size. Stay standing up, and wrap the tape measure around the fullest part of your breasts. (Keep the tape as horizontal as possible — make sure that it's not sagging around your back.) Subtract your band size from this new number to calculate your cup size:
    • Less than 1 inch = AA
    • 1 inch (2.5 cm) = A
    • 2 inches (5 cm) = B
    • 3 inches (7.5 cm) = C
    • 4 inches (10 cm) = D
    • 5 inches (12.5 cm) = DD
    • 6 inches (15 cm) = DDD (E in UK sizing)
    • 7 inches (18 cm) = DDDD/F (F in UK sizing)
    • 8 inches (20.5) = G/H (FF in UK sizing)
    • 9 inches (23 cm) = I/J (G in UK sizing)
    • 10 inches (25.5 cm) = J (GG in UK sizing)


  • Don't be tempted to buy the wrong size or a poorer quality bra because it's cheaper. With bras you generally get what you pay for. It's better to have one bra that fits really well, than three that are uncomfortable!
  • If you want your bras to last and keep their fit, never wear the same bra two days in a row, even if it has been washed. You should have at least three bras which you can wash and wear in rotation, allowing the elastic to fully recover before it is put under stress again.
  • Do not expect to need the same size in every style of bra, or to able to buy any bra in your "true size" without having to try it on. Different styles will suit different breast shapes, so two women who wear the same size in one bra might need different sizes in another bra.
  • A well-fitted bra should provide 90 percent of the support from the band, and the straps the remaining 10 percent.
  • If you have uneven cup sizes, go with the bigger side. You can support the smaller breast by making that shoulder strap slightly shorter. If you have a significant size difference, there's always the option of wearing a silicone bra insert or removable padding in the smaller side.
  • Ignore anyone who tries to tell your definitive size from your measurements alone - especially if they tell you to add several inches to your underbust measurement. Just like dress sizes, bra sizing has changed over the years, and the old method does not work for modern bras.
  • This is only to give you a rough idea of what size to try on first - the fit is more important than the number on the tape measure. Because women are all different shapes, two women with the same measurements will often need a very different bra size.
  • D+ cups will benefit from bras with seams. The reinforced side panels will provide a narrower look, thus slimming your torso.
  • Many bra companies like to pretend that sub-28 sizes do not exist. However, many women really do wear bra bands sized 20, 22, 24, and 26. Some even smaller. Keep in mind, the material will stretch. Unfortunately, because the bra companies like to pretend that smaller bands do not exist since it is more profitable to them, it is almost impossible to find those sizes. Your best bets are to get a bra altered, which may not work because of the wires and how they might then dig in to your body. If you have a bra tailored, get a bra that is up one band size and down two cup sizes. As band and cups are proportionate to one another, a cup on a larger band will have larger wires. This is why you will want the smaller cups, for the smaller wires. *Cup sizes above D tend to vary significantly between manufacturers, so check with the retailer or look for customer reviews before you buy online.

Things You'll Need

  • Soft tape measure
  • Bras to try on

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