When you're building a house, it's critical to have a solid foundation on which to build. It's the same with finding the right bra for your body type. A proper fitting will involve determining your bra band size and your bra cup size. Knowing these will allow you to choose a bra that can improve your bra comfort and your posture, make your clothes fit better, and emphasize or downplay your assets, according to your needs.
The first step in measuring for bra size is to determine your bra band size. To do this, use a tailor's measuring tape and circle your ribcage under your breasts, where your bra band rests; it's important that the tape rests flat against your body. Once you have this number in inches (centimeters), add five if it's an even number and six if it's odd. This is your bra band size, and you're halfway there. Remember this number or write it down, because it will also help you figure out your bra cup size.
![](http://images.wisegeek.com/slideshow-mobile-small/trying-a-bra-for-size.jpg)
Next, measure around your back and across the center of your bustline, taking care to keep the measuring tape flat and parallel to your bra band line. Subtract your bra band size number from this second number to find out your bra cup size. Cup sizes increase based on the number of inches (centimeters) of difference in this formula. One inch (2.54 cm) equals an A cup, 2 inches (5.08 cm) equals a B, three inches (7.62 cm) equals a C, and so on.
![](http://images.wisegeek.com/slideshow-mobile-small/pink-sports-bra.jpg)
While fairly easy, measuring for bra size can be an intimidating prospect, but there are trained professionals in most department stores who can help you figure it all out more easily than you could alone. You can ask for a bra fitting at most stores with a good size lingerie department, or ask at a boutique that may specialize in measuring for bra size. Most stores don't require an appointment, and many can help you find the right bra size in just minutes.
![](http://images.wisegeek.com/slideshow-mobile-small/beige-underwire-bra.jpg)
You can ask to be measured with your clothes on, if you're more modest. A good professional can get accurate measurements efficiently and objectively by measuring you with or without your current bra. You can also ask a friend or relative to help you determine your measurements, though many women find they get the best results, and the best fit, by working with a professional fitter.
![](http://images.wisegeek.com/slideshow-mobile-small/purple-strapless-bra.jpg)
Every woman is unique, and a fitting professional can help answer questions when you're finished measuring for bra size. You may want more information about how to fit a bust with two different cup sizes or how to find a less common size; you may also want help finding the right sports bra for your workout needs. There are hundreds of variations, so be sure to ask questions about fit, comfort, cost, and utility. Unlike most items of clothing, a bra is designed to be worn over and over, so it's important to find a few that will suit your lifestyle and fashion needs.
![](http://images.wisegeek.com/slideshow-mobile-small/tape-measure.jpg)
Even once you're finished measuring for bra size and feel confident you know which one to buy, it's still important to try bras on before you make a purchase. Bodies also change shape with age and activity, so you may need to be measured again if you find your fit is failing. Replacing a bra that is wearing out also is critical to a proper fit.