As a professional bra fitter, I often notice how customers wear bras with too large a band size and too small a cup size. If the average person buys a 36B bra, they may actually need a 34D or even DD. To size yourself, you will need a soft measuring tape because it provides the most accurate measurements. To begin, remove your bra. If you visit a lingerie store for a fitting, most either fit over your existing bra or by eye, but if you are measuring yourself, this method yields better results. For a quick and easy way to determine a starting point size, please visit my bra size calculator or check out the video below:
Measure directly underneath your breasts on the rib cage, making sure to keep the tape level all the way around your torso. Pull the two sides together until they meet and lie flat against your body, but be careful not to pull too tightly. The tape should feel snug, but not constricting.
Now, we need account for your personal preference on how your band should fit. If you prefer a snug fit, then your ribcage measurement becomes your band size. If you prefer a looser but still snug fit, add 2″ to your measurement, and if tightness irritates you, add 4″. Note that if you are between two sizes, e.g., 31″, you can size up or down to the nearest band.
As an example, if you measured 32″ around the ribs, then you can try a 32 band for a tighter fit, a 34 band for a moderately tight fit, or a 36 band for slightly looser fit. Keep in mind, however, that bras do lose elasticity over time and will only become less supportive with wear. Most people who prefer to add 4″ to the band measurement have muscular or thin rib cages without extra padding and usually wear smaller cups.
Inflammation and chronic illness can also impact the way a band feels, and while support is the goal, your comfort is paramount. That said, if you have larger breasts, you may want to avoid adding 4″ and instead rely on an extender until the bra has time to conform to your body. About 80% of the support for your breasts comes from having a snug band.
Next, measure lightly around the fullest part of your breasts (usually across the nipples), making sure not to compress any breast tissue, and round up to the nearest number.
For example, a measurement of 40.5″ would be rounded to 41″. To find your cup size, subtract the band size from the measurement taken across your bust. Then, use the chart below to find your corresponding cup size:
| Measurement (in.) | US Size | UK Size |
| 1 | A | A |
| 2 | B | B |
| 3 | C | C |
| 4 | D | D |
| 5 | DD/E | DD |
| 6 | DDD/F | E |
| 7 | G | F |
| 8 | H | FF |
| 9 | I | G |
| 10 | J | GG |
| 11 | K | H |
| 12 | L | HH |
| 13 | M | J |
| 14 | N | JJ |
| 15 | O | K |
| 16 | P | KK |
If you needed to size up in the band to accommodate your preference, subtract your original band size from your bust measurement to ensure adequate space in the cup. Then size up the band to your comfort level. Remember to reduce the cup by one for every band size you go up. For example, a person who prefers to add 4″ to the band but measures 30″ around the ribs and 35″ around the bust should start with 30DD then move to 32D before finishing at 34C.
This fitting technique, as well as our bra size calculator, is only meant to provide a starting point size. Breast shape, personal preferences, and even age can affect what size you need, and because manufacturers utilize different cuts and sizing guides, finding the right fit can be challenging.
Examples of Poorly Fitting Bras
Double Check the Fit
Now that you have a general idea about what size you need, review these tips to ensure you have the proper fit.
- Your band should fit snug (but not tight) on the loosest set of hooks. The elastic in all bras deteriorates with daily wear, and the bra will last longer if your start with a snug band.
- The band of your bra should be centered across your back with the straps adjusted to the tops of the shoulders. It should not ride up the back or cause the straps to fall off the shoulders.
- Adjust your straps. Again, the majority of weight is supported by your band, but you may need to adjust your straps looser or tighter to provide you with optimal support and comfort. Properly fitted straps will pull the cup against your breast without gaping or overflow.
- Check your underwire. The underwire of a bra should encase the breasts and rest firmly against your ribcage, especially in the center where the underwire meets (known in the biz as “tacking”). The wire should lie flat, completely separating your breasts. On the side of your torso, the wire should not mash your breasts or dig into the skin. Many people do not realize that there is breast tissue on the side that needs to be scooped into the cups as well. When the bra fits properly, the cup of the bra should enclose the breast tissue and be filled out and shaped by your breasts.
- The cups should not allow breast tissue to spill over the top or the sides nor should they pucker or gape. Also, there should not be significant extra space between the underwire at the bottom or the side and your breast tissue. If you have narrow roots, meaning the majority of your breast tissue is on the front of the chest and not the side, space between the wire and tissue may be unavoidable. Provided it does not cause any discomfort, I consider this a “fit quibble.”
- Anyone needing wireless bras may experience fit issues, particularly in higher cup sizes, because the bra design and construction changes. In general, the band should still fit snug on the loosest set of hooks without any gaping, puckering, or overflow at the cups. The band should sit beneath breast tissue to provide lift, but the center may not sit flat against the ribcage. Breast tissue on the side should be fully scooped into the cups without overflow, and the straps should be adjusted as with a wired bra. If the bra has side stays, watch the location to ensure they do not compress or dig into breast tissue, and while the underwire is no longer present, the cup itself should match your tissue shape as closely as possible to improve the fit.
Examples of Properly Fitted Bras
Common Bra Fitting Problems
&
How to Fix Them
Problem: Your breasts pop out the bottom of the bra, especially when you raise your arms.
Solution: Try the next cup size up and scoop breast tissue up into the cup so that it is completely encased and does not fall out the bottom. The band may also too big. Check that it feels snug on the loosest set of hooks.
Problem: Your breasts overflow from the cups of the bra.
Solution: Size up in the cup until all of your breast tissue is covered. Also, the style of the bra may not be right for you. Some cups are designed to be shallower near the top or they have reduced stretch, which can cut into breast tissue.
Problem: The straps of your bra give you deep shoulder indentations.
Solution: Loosen the straps and examine the band. At least 80% of the support from your breasts comes from the band, and if it is too loose, you may be tightening your straps to compensate for the loss of support
Problem: The band rides up in the back.
Solution: Size down in the band, but remember you also need to size up in the cup, e.g., a 34C becomes a 32D.
Problem: Your breasts are smashed together at the center of the bra or compressed by the underwire on the sides.
Solution: Size up in the cup. The underwire should ideally not lay on any of your breast tissue. The center should sit flat against your breast plate, and the underwire should encase the tissue on the sides, not compress it. However, if you have full, center-set tissue, the underwire may not sit flat in fuller-coverage styles, especially if the center is wide and shallow. If possible, look for bras with a lower height at the center gore where the underwires meet. If you wear bras in the upper end of the cup size spectrum, true tacking may not be possible.
Problem: The underwire digs into the your breasts or sides.
Solution: You may need to size up in the cup to ensure the underwire sits behind the breast tissue, but the style of bra may not be right for your body. Some bras have a higher wing or cup near the side, which can dig into the skin or chafe. Look for a style with a lower wing if the cup size fits.
Problem: You have extra space between where the cup ends and where your breast tissue starts on the side.
Solution: The shape of the cup is too wide for you. If the cup size fits otherwise, consider looking for styles with narrower cup shapes, possibly with added center projection.
Problem: You have frequent infections, rashes, or break outs underneath the breasts.
Solution: Size up in the cup and evaluate your band. Infections or rashes under the breasts are usually a result of breast tissue being trapped against your skin for long hours, which could mean your breasts are falling out the bottom of your bra.
Bra Fitting for People AMAB
(Assigned Male At Birth)
Sometimes people AMAB have broader ribcages and shallower breasts than those AFAB (Assigned Female At Birth) which impacts bra fit. If you have gynecomastia, the above advice frequently works because gynecomastia is characterized as the development of breast tissue in AMAB people. In the future, I plan to write a more comprehensive gynecomastia centric article. Similarly, hormone therapy for Trans women can also cause the development of breasts which makes bra shopping easier.
However, there are no absolutes, and the three most common problems I notice are:
- The “Large Band & Small Cup” Bra Desert: Manufacturers conveniently think that anyone wearing a 38+ band must also wear at least a C or D cup. Abysmal selection can make it challenging to find anything in your size. Consider brands like Amoena, Anita, Curvy Couture, Elomi, Glamorise, Goddess, Marie Jo, Natori, Prima Donna, and Wacoal who offer a broader range of sizes as well as vertically integrated plus-size retailers like Torrid or Lane Bryant.
- The “Too Tall Cups” Problem: The breast tissue for people AMAB, even with hormones, can sometimes be shallow at the top, meaning you may need a B or C cup to fill out the lower and side cup. However, there can be a massive gap or wrinkling where the cup doesn’t contour properly at the top of the breast. Try to find styles that are either more of a demi, i.e., a half-cup shape that isn’t as vertically long, or a plunge with a sloped upper cup designed to sit flatter against the breast.
- The “Wings are Too Short” Dilemma: If you have a broader back or rib cage, the underwire and side of the cup may extend further back on the side than needed. If possible, try to look at styles which have a narrower frontal placement of the underwire and cups with longer wings.
Finally, I want to note these problems exist for people AFAB too. There’s nothing wrong with your body. The only reason I included a special section here is because as a fitter, I frequently need to address these problems for my clients and want the information available.
Bra Fitting: Does it have to be perfect?
Or Alternatively Titled:
In which Erica undermines all of the above advice
There’s a polarizing term in the bra fitting community called a “bravangelist,” a portmanteau of “bra” and “evangelist.” Depending on whom you are in the intimate apparel industry, the term either describes your entire mantra, causes you no end of irritation, or inspires a middle ground stance. When I first started fitting bras, I was firmly in #teambravangelist because I saw how powerful and wonderful finding the right bra size could be, both personally and professionally. The first person I ever fit, apart from myself, was my mom who grudgingly went through the process and bought the 38 bands she felt were too snug. After her first day wearing them, her coworkers asked if she lost weight, and she immediately purchased more. It was my first success as a bra fitter, and I relied on that mentality when I opened the shop.
Of course, part of experience is learning that your views are not applicable to every situation or person. Some people, whether for health, occupational, or personal reasons, cannot stand a snug band. In fact, for months after I had the Covid-19 Delta variant, my normal, comfortably tight bands caused pain and tightness in my chest, and I needed to wear one, sometimes two, extenders. Others prefer a band which is a size tighter than they measure because they have more compressible tissue around the ribs and/or heavier breasts. Some people absolutely refuse to wear anything other than molded foam cups or padded bras even if the shape isn’t the best. Others only want a minimizer to compress tissue.
Tissue and breast shape also contribute to the need for compromise. Close set breasts may never be parted by underwire and instead slide back together. A heavier gauge wire can sometimes correct this as can a lower neckline, but maybe neither of those things are what you or the client wants. Maybe there aren’t other options in that size.
Then there’s the bras themselves. Certain styles I call “fitter’s bras” because they work on most breast shapes, tissue types, and sizes. Store owners have another name for them: best-sellers. They just work. These bras are awesome, but what if you or the client wants something special, something a little different? Maybe that something different doesn’t fit perfectly. Maybe it’s just okay, or maybe you have to sister size to wear it. Maybe the manufacturer designed the bra as a “fun” piece rather than an everyday bra, meaning a broad-range fit wasn’t a priority. What do you do then? For every person, there are often unique, sometimes contradictory requirements. As a fitter, my job is to tease out what is possible and find the best solution.
If you are a bravangelist type fitter or person, this can be enormously frustrating because your focus will be on attaining perfection, or at least as close as possible. But bodies, boobs, and people do not always behave the way you think they should, and if you are inflexible, it can lead to disappointment.
As I was in business longer and interacted with more people, I realized for every rule there are exceptions. If you love it, even if if the fit isn’t perfect, wear the damn bra and be happy. If you are a fitter and your client is having a lot of fit issues because nothing is quite made for them, be more flexible with what you consider the best fit and listen to what the client says. If they feel good about themselves and the bra, then that is the best you can do . . . at least until more options are available for them. I want to note this is not an excuse for unscrupulous fitters to bullshit customers, but more an observation that perfection is seldom attainable and even overrated.
To answer the question posed above: No, your bra does not have to fit perfectly. Your bra should fit you as comfortably as possible. If that means you get a soft tack in the center or your band is looser than the industry standard, so be it. It’s your bra after all. If you’re happy, that’s what matters.