What the Experts Know About the Proper Bra Fit

Expert Advice on the Proper Cup Size

Bras for the most part are highly engineered and thoughtfully designed. It's not unusual for a bra design to be composed of as many as 40 pieces and findings. Though many bras are beautiful, bras are more about playing a supporting role than they are about fashion. We women need to understand what we are looking at when we try on a bra. Knowing what design features work best for our figure type will help us more easily identify the style of bra that suits our needs best.

Choose the Proper Cup Size

While the underwire defines your breast's diameter, a cup size defines your breast's projection or cup depth. Cup sizing is alphabetical - A, B, C, D etc. After the D size, however, manufacturers do not all agree on what to name subsequent sizes. Generally, American manufacturers prefer D, DD, DDD, DDDD. European manufacturers tend to prefer D, E, F, G. If your cup size is larger than a D, it can be confusing to determine what size bra to purchase, especially if the manufacturer has a unique sizing convention.

HerRoom has made this easier for you. We've compiled a chart comparing all plus size manufacturers' cup sizing conventions. Simply refer to our chart to determine your correct cup size in that brand.

It is also a good idea to know how many sizes larger than a D cup you are. That way if you come across a bra with unusual sizing, you can tell your salesperson you are 2, 5 or whatever cup sizes larger than a D cup. She will then be able to ascertain your correct cup size in that style.

There are 2 important things to know about cup size.

The first is that a cup size on one band size is not equal to the same cup size on another band size. In other words, a 32D bra has smaller cup volume and diameter than a 34D bra yet both are a D cup. So I bet you're wondering why the industry assigns the same cup size to both.

Well, cup size is a measurement of how far your breasts project from your chest wall. Each cup size denotes a 1" increase in your body's circumference around your bust line. Knowing this fact can help you zero in on your correct bra size. For example, you try on a bra and the band feels comfortable, but your breasts are spilling out. Keep going up in cup sizes on the same band size until you find the bra that fits. Alternately, the cups fit great, but the band is too big. When you go down a band size, you now know that you need to go up a cup size to maintain the same underwire diameter and similar cup volume (Example: Go from a 40C to a 38D).

The second important point about cup size pertains to women with cup sizes larger than a D cup. Trying to find cup equivalents among brands can be very difficult. In one brand you are a DDDD, but this same cup size can be a G, F, or FF in other brands. The first thing you should know is that all manufacturers size their cups up by 1" circumference increases. They may call their sizing by different letters, but the increases between sizes are uniform. So, as mentioned above, find out how many cup sizes above a D you are. On our site, when you look at the sizes available in a particular bra, we display the cup sizes in order from smallest to largest. If you are 4 cup sizes larger than a D cup, you can count 4 sizes from D to find your correct size in that particular brand.

The Cup Size Game.

Finding a bra you love and discovering its size range stops just before your size can be frustrating. However, you may not be totally out of luck. Say you are a 40C and the bra you have found stops at 38DD. You MIGHT be able to wear the 38D or 38DD in that bra if the band doesn't feel too tight. Deviating from your traditional bra size is called the cup size game. Substituting bra sizes will work more successfully on women with band sizes 40 and above and D cups or larger because there is more breast tissue and body circumference to work with - a 2" band increase or a 1" bust line circumference increase is not as significant as it would be on a smaller framed person. However, having shared this game with you, it is always best to purchase your true size if you want to maximize proper fit.

A final thought about cup sizes.

When a manufacturer grades his patterns to create different sizes for a bra style, he moves the bust points slightly wider with each cup size increase. B cup bust points are 1/2" farther apart than A cups. Bust points get 1/4" farther apart between B, C and D cups, and 1/8" farther apart with larger cup sizes.