C Cup vs D Cup Bra Sizes In Review

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Shopping for a bra, and they don’t have your size? Thinking that maybe you can get away with a D cup instead of your C cup? Let’s find out! 

There are many benefits to wearing a bra, and the size of the bra can be an important factor.

The difference between C cups and D cups is that C cups are smaller than D cups. The volume of a C cup is also less than that of a D cup.

C Cup versus D Cup General Overview

C cup and D cup bras are not interchangeable. Before you purchase that new bra, you should probably get a bra fitting or at least find out your measurements. If you are shopping in-store, there may be a bra-fit specialist who can help you determine your size.

If you don’t want to go that route, you can measure yourself.  While standing, use a measuring tape to measure around your rib cage just under your bust where the band of a bra would usually sit. The measuring tape should feel snug, but not tight.

Measure in inches: if you land at an even number, that is your band size. If it’s an odd number, round up to the closest even number. Next measure again, but this time at the fullest part of your bust.  Then subtract your band size from this bust measurement.

Woman sitting on a couch wearing a beige colored bra

The difference between the band and bust size will give your cup size.  With a C cup, there is a difference of 3 inches, while with a D cup there is a 4 inch difference. Now that you have your band and cup size you are ready to shop.

It’s best to re-measure yourself every time you are planning on purchasing bras, as your bra size can change over time due to weight gain or weight loss. You should also keep in mind that different bras fit differently. You should always try a bra on before purchasing.  A 36 D bra from one store may not fit the same as a 36 D bra from another store.

Let’s talk about the C Cup:

A C cup is not considered a large cup size. It’s smaller than the average cup size among American women, which is a DD cup. There is a 3-inch difference between the bust and the band size of a C cup.

Depending on your body type and rib cage size,  C cup breasts can appear bigger or smaller. If you have a smaller rib cage, a C cup will look bigger. If you have a large rib cage, a C cup will look smaller.

What about the D Cup?:

A D cup is an inch bigger than a C cup when it comes to the band size. The D cup is also 1 to 2 inches smaller than DD and DDD cups. In the UK, they call DD and DDD cups E and F cups. A D cup can be considered large but not overwhelmingly large.

D cups can highlight your curves and accentuate your upper body. Just like with a C cup, how the D cup looks on a person depends on their figure and chest size. For a petite woman, D cups may seem like they are quite large, while the same cup size on a  full-figured lady will end up looking average.

Similarities and Differences

C cup and D cup differ in underbust circumference by an inch. A C cup has a 3-inch difference between the bust and band size, while the D cup has a 4-inch difference. C cup breasts will also weigh a few pounds less than D cups.

Both a C cup and a D cup can look bigger on a petite woman and smaller on a full-figured woman.

C cup and D cup bras are considered to be average sizes that are easily found for purchase in stores and online depending on the band size needed. The band size of the bra can quickly change their availability, as band sizes can measure from 26 to 64 inches.  The most easily found band sizes range from 30-40 inches. Anything above or below those measurements can mean you may need to find a specialty store for your bras. 

Sister Sizes:

Having issues finding your bra size? You can get a sister size! Finding a sister size requires a set of one-size shifts, in opposite directions. This means you can also wear a bra with the next smallest band size as long you use the next cup size up.

If your measurements are a  36 C, you can also wear a 34 D and so on. You definitely want to try the bra on when you are going to be using your sister size, so you can confirm the bra fits just right. A bra that fits perfectly can provide you with great support and comfort.

Close-up photo of a woman wearing beige colored bra

How to Know if My Bra Fits Perfectly?

Having a bra that fits properly is essential to your comfort. You want to make sure the band and cup sizes are not too tight, and not too loose. A too tight cup or band can be painful while a too loose fit does not support your breasts adequately.

If your bra fits properly, the straps should not slip off your shoulders. A well-fitting bra will hold and support your breasts within the cups with no overflow.

We have listed a few things that you need to remember when looking for a bra below.

The Band and Straps

The band is the most important part of the bra. Almost 80 to 90% of the support a bra can give your breasts comes from the band. The band should not be too tight, but should still be snug on your torso. For the best fit, you should be able to slip two fingers between your skin and the bra. A band that fits should not move up towards your breasts when you’re moving around or when raising your arms. 

The rest of the support a bra can give you comes from the straps. Bra straps are there to make your breasts appear even and help to hold them up. Bra straps should not be so tight as to dig into your shoulders, but should be tight enough to help support your breasts. Most bras available have adjustable straps.

Woman wearing beige colored bra

The Cup

No matter your cup size, your breasts should fit inside of the bra. The proper cup for your breasts should not cause any spillage on the sides, top, or bottom of the bra. You also want to make sure that you don’t get too big of a cup for your breasts. If the cup is too big, your breast will not fill the cup of the bra out entirely. This can make the extra fabric in bra cup area wrinkle and will show through your clothing.

The gore (front center) of the bra should be flat against your sternum. If the gore does not rest on your sternum you need to go up a size.  If you’re wearing a bra with underwires, it should fit comfortably. The underwires should not be poking the sides of your breast, or underarm.

Which Cup Size Is Better?

The best size that you can wear will always depend on the needs of your breasts. A well-fitted bra will look great on you whether it is a C or a D. With a good fitting bra you will feel little to no discomfort  and  you should be able to wear it all day with no issues. A bra  that is the right size for you should be able to give your breasts plenty of support and security.


Hi there, I’m Allena, Founder and Editor of The Better Fit. I’ve always had a passion for finding ways to help women improve various areas of their lives. I have researched and worked to create this website so women would have a place to come and be informed about an article of clothing they literally wear every day.