We all need a little extra support, but the better a bra fits you, the greater chance you have of being comfortable wearing it. According to some study, 85% of women are wearing bras that don’t fit properly. There’s no real metric for what a “properly fitted bra” actually is, so bra fit advice is kind of like being in The Matrix, as even though most women wear them, nobody can explain how they decided that it was the right size for them. Since there is no standard practice in bra measuring and manufacturing and no one is really sure why, and cup size should be measured by volume, not visual projection. Accurate volumetric measurement is difficult and very few women want strangers handling their bare breasts, so a “plus four” method was established. The problem is that this method was designed in the 1950s when bras were made from silk and satin and did not stretch. The 4 inches extra allowed breathing room, something which is completely redundant today, as all bras now have elastic and stretch in them.
It is not easy being a woman especially when it comes to finding the right bra. Some manufactures determine bra cup size by the difference between full bust and underbust girths. However, other brands use chest circumference instead of the underbust girth. Underbust girth is measured horizontally from where the breast meets the rib cage, while chest circumference is measured from underneath the armpit across the upper chest and back. Another challenge comes from how to convert the girth difference into letter-graded cup size. Each company goes with different amounts of offsets, and typically this ranges between 0 to 6 inches so the girth difference is manipulated and depending on the shapes of breasts, any cup calculation may result in inaccurate cup size, because of inconsistent intervals between cup sizes.
Some manufactures are investigating magnetic resonance imaging to define the breast region in a three-dimensional space, but in order to acquire accurate breast volume from a body scan, it is necessary to have a reasonable method to determine a breast boundary. The boundary makes it possible to separate the breast from the neighboring body structures, such as shoulder, armpit, and upper abdomen. Due to the shape of breasts and the effect of gravity, the lower arc of the boundary is visible and easy to define in smaller breasts, and for larger breasts, the lower arc becomes visible if the breast is lifted up. Aristotle used water displacement to determine volume and this type of method could also be used to get an accurate measurement of cup size.
A good-quality, well-adjusted bra in the right size can make all the difference, both in comfort and appearance. Breasts come in a wide range of shapes and sizes. No two people have breasts that look exactly the same. The right bra is one that fits perfectly, but in the world of braziers, getting the correct fit is not always simple. The wrong bra can ruin an outfit while the right bra isn’t noticeable. It is really easy to wear the wrong bra size, but it can be difficult to realize when the size you selected is not the right fit for you. Using the traditional way to size a bra is done with a combination of letters and numbers and it takes three steps, one for the band, one for the bust and then cup size is calculated from these measurements. The number portion of the size (the 34 in 34C for example) represents your band size or the measurement around your rib cage just below your breasts. The letter portion of your bra size is your cup size and this is where things can get a little tricky.
Measure your band while you are wearing a lightly lined (non-push-up) bra, but being topless for this will ensure you’re measuring your breasts at their most natural position. Start by wrapping a soft measuring tape directly under your breasts. Make sure that you stand up straight and that the tape measure is directly parallel with the with the ground. You should be able to comfortably run two fingers under both sides of the bra at the same time. If the bra pulls away from your body easily, it is too loose. If you have trouble getting your fingers under the band and it feels uncomfortable, it is too tight. The band is what mostly supports your breasts, not the straps. Round the measurement to the nearest whole number and you’ve got your band size. Depending on the manufacturer, you may need to add four if the measurement is even and add five if the number is odd. So, if you measured 34 inches, your band size would be 38, and if you measured 27 inches, your band size would be 32.
In step two, you measure your bust. Place the tape at the fullest part of your bust. Make sure it’s parallel to your band again. Subtract the band size from your bust size to find the right cup size. Every inch will equal one cup size up, so an A cup means your breasts are lifted an inch of your chest, and a B cup means they are lifted 2 inches off your chest. Any cup with a 34 band size is considered a “true cup” size. This means that a 34AA is in fact a AA cup, just as how a 34B is a true B cup. However, a 34B is also equivalent in cup volume to a 30D, 32C, and a 36A. All three aforementioned sizes are a B cup despite what their cup letter indicates. As the band size gets bigger, the cup also gets bigger, so a 36B bra has bigger cups than a 34B bra. Sister sizing which are groups of bra-size equivalents that are related by cup volume also comes into play where you select one actual size larger than your current Band size and one letter name smaller than your current Cup. Finding the right bra size can be a lot like Alice in Wonderland eating mushrooms to get bigger and smaller.