Know Your Sister Size Bra: Find the Perfect Fit & Enhance Comfort

There are times when the bra size you regularly opt for doesn’t fit you. Ever wondered why you face this situation in spite of buying the bra size you’ve bought a million times before? Well, remember that several factors, such as the bra fabric, manufacturing variations, presence of underwires, cup shapes, and padding levels, might contribute to the way a bra fits you. This is where the concept of sister size comes into play.

What Is Sister Sizing?

Sister sizes can be a savior when the bra in your actual size doesn’t fit properly. In simple terms, sister sizes are equivalent bra sizes. The cup volume of your actual bra size and sister size bra remains the same. That’s why fitting experts recommend trying sister sizes when your original bra size doesn’t fit or is unavailable. I Want to Know My Sister Size Every bra size has four sister sizes, but when selecting sister-size bras, you can ideally consider the nearest two for the best fit. Sister Size Up For instance, if your bra size is 34C, your sister size up will be 36B (one band size higher and one cup size smaller). Sister Size Down Similarly, if your cup size is 34C, your sister down will be 32D (one band size lower and one cup size bigger). Opt for a sister size up when the band of your actual size bra is tight or too small. On the other hand, go for a sister size down when your cup is too small. Shyaway Bra Sister Size Chart Sister sizes are essentially related sizes with different band sizes but the same cup volume. Your sister sizes would be 32D (going down a band size while increasing the cup size) or 36B (going up a band size while reducing the cup size), for instance if your typical size is 34C. When buying bras online, this bra sister size chart is especially helpful because it guarantees that you can still find a supportive and comfortable fit even if your desired size isn’t available or in stock. Looking for your perfect bra size? Shyaway bra size calculator will help you to measure your bra size.

Bra Size	Sister Size Up	Sister Size Down
30 Bra Band Size Means A 30 Bra Size refers to the measurement around the rib cage just underneath the bust. It indicates the band size of a bra and is typically associated with a smaller frame. A 30 band size is considered relatively petite and may be suitable for individuals with a smaller rib cage measurement.
30A	32AA	28B
30B	32A	28C
30C	32B	28D
30D	32C	28DD
32 Bra Band Size Means A 32 Bra Band Size refers to the measurement around the rib cage just underneath the bust. It represents the band size of a bra and is commonly associated with individuals who have a slightly larger rib cage measurement compared to smaller band sizes like 30 or 28.
32A	34AA	30B
32B	34A	30C
32C	34B	30D
32D	34C	30DD
32DD	34D	30DDD
34 Bra Band Size Means A 34 Bra Band Size refers to the measurement around the rib cage just underneath the bust, which determines the band size of a bra. Specifically, a 34 band size corresponds to a rib cage measurement of approximately 34 inches. For example, a bra labeled as “34C” indicates a band size of 34 inches and a cup size of C.
34A	36AA	32B
34B	36A	32C
34C	36B	32D
34D	36C	30DD
34DD	36D	32DDD
36 Bra Band Size Means The measurement around the rib cage directly beneath the bust defines the band size of a bra, and that measurement is known as a 34 bra band size. More specifically, a rib cage of about 34 inches is matched to a 34 band size.
36A	38AA	34B
36B	38A	34C
36C	38B	34D
36D	38C	34DD
36DD	38D	34DDD
38 Bra Band Size Means A 38 Bra Band Size signifies a measurement around the rib cage of approximately 38 inches, indicating a larger band size. This size provides essential support for the bra and should fit comfortably around the torso. When paired with the appropriate cup size, such as “38C,” it ensures a proper fit and comfortable wear.
38A	40AA	36B
38B	40A	36C
38C	40B	36D
38D	40C	36DD
40 Bra Band Size Means A 40 Bra Band Size denotes a ribcage measurement of approximately 40 inches just below the bust. This band size is paired with various cup sizes (such as A, B, C, etc.) to form the complete bra size, which accommodates different bust dimensions.
40A	42AA	38B
40B	42A	38C
40C	42B	38D
40D	42C	38DD
40DD	42D	38DDD
42 Bra Band Size Means A 42 Bra Band Size refers to the circumference of the ribcage just below the bust, measuring approximately 42 inches. This band size is often paired with various cup sizes (such as A, B, C, etc.) to determine the overall bra size, which accommodates different bust measurements
42A	44AA	40B
42B	44A	40C
42C	44B	40D
42D	44C	40DD
42DD	44D	40DDD
44 Bra Band Size Means A 44 Bra Band Size indicates that the circumference of the ribcage, just below the bust, measures approximately 44 inches. This band size is combined with different cup sizes (like A, B, C, etc.) to create the full bra size, catering to various bust measurements
44A	46AA	42B
44B	46A	42C
44C	46B	42D
44D	46C	42DD

Should I Definitely Opt for Sister Size Bras?

1. Please remember that there are many reasons why a sizing bra doesn’t fit you. Note which attributes of your bra need to be corrected in order to achieve the right fit. This will help you get a bra that fits the way it should.
2. It is also important to understand the physical changes in your body that may lead to a misfit. Puberty and pregnancy are stages when your normal bra would do no justice. So, trying sister sizes would be the ideal option here.
3. Moreover, an ill-fitting bra can cause a lot of discomfort, neck and shoulder pain, and posture problems. So, it is better that you go for sister sizes rather than stick with the same uncomfortable bra.
4. If you are still not satisfied with the sister sizing concept, we recommend you measure yourself again for the correct bra size before proceeding with the shopping.

The Most Common Sister Size Questions Answered

1. Do Sister Sizes Really Work?

Yes, sister sizes work well, but there is a certain limit to them. With sister sizing, you can either go one size up or down, but you can’t choose two or more sizes. Going beyond that will change the overall proportion of the bra, resulting in a poor fit.

2. Is the DD cup size the same as the E-cup size?

No. Both the cup sizes come in the same size, but the size of the band may vary.

3. How Do Sister Sizes Work?

• Sister Size Up

“Sister size up” means one size larger than your current band size and one letter smaller than your current cup size. For example, if your bra size is 34C, then your next size up will be 36B.

• Sister Size Down

“Sister size down” means one size smaller than your current band size and one letter larger than your current cup. For example: if your size is 34C, your sister size down will be 32D.

4. Should I go up a Cup Size or Band Size?

The proper cup fit is determined by the band size. If the band size changes, so does the cup size. For every band size, if you go one size down, you must go one size up in the cup.