If you’ve found that finding your right bra size is a frustrating process, there are some sizing hacks that can make finding your perfect fit much easier. One of the most effective of these is the use of “Bra Sister Sizes”. You may be unaware that every bra size has several "Sister Sizes"- these are sizes which have an equivalent cup capacity, despite the letter of the cup size being different. Knowing your sister sizes can help you find your best fit when buying bras that run smaller or larger than normal.
It’s a common misconception that the larger the cup size, the larger the bra, no matter what the band size (i.e. a 32F is larger than a 36B, a 34C is larger than a 38A, etc). However, this is not the case. During the bra manufacturing process the same exact bra cup may be paired with different band lengths to create multiple bra sizes. For example, the same exact cup is used to make 38A, 36B, 34C, 32D, AND 32DD bras! The reason for this is that within each cup size (A, B, C, D, DD, etc), as the band size increases, the cup size also slightly increases even though the letter does not. For example, a 34B bra and 36B bra will not only have different lengths, but the capacity of the cups will also differ. Once you understand that there are equivalent “sister sizes” to your own bra size, it can help you solve any bra fitting issues you may have.
Bra Sister Size Size Comparison Chart:
Each row shares the same cup size and each column shares the same band size.
Sizes in black are sizes we make. Sizes in light gray are sizes we dont make.
| 30 BAND SIZES | ||
|---|---|---|
Sister Size DOWN | Current Bra Size | Sister size UP |
28B | 30A | 32AA |
28C | 30B | 32A |
28D | 30C | 32B |
28DD | 30D | 32C |
| 32 BAND SIZES | ||
|---|---|---|
Sister Size DOWN | Current Bra Size | Sister size UP |
30B | 32A | 34AA |
30C | 32B | 34A |
30D | 32C | 34B |
30DD | 32D | 34C |
30DDD | 32DD | 34D |
30F | 32DDD | 34DD |
| 34 BAND SIZES | ||
|---|---|---|
Sister Size DOWN | Current Bra Size | Sister size UP |
32B | 34A | 36AA |
32C | 34B | 36A |
32D | 34C | 36B |
32DD | 34D | 36C |
32DDD | 34DD | 36D |
32F | 34DDD | 36DD |
| 36 BAND SIZES | ||
|---|---|---|
Sister Size DOWN | Current Bra Size | Sister size UP |
34B | 36A | 38AA |
34C | 36B | 38A |
34D | 36C | 38B |
34DD | 36D | 38C |
34DDD | 36DD | 38D |
34F | 36DDD | 38DD |
| 38 BAND SIZES | ||
|---|---|---|
Sister Size DOWN | Current Bra Size | Sister size UP |
36B | 38A | 40AA |
36C | 38B | 40A |
36D | 38C | 40B |
36DD | 38D | 40C |
Three Common Fit Problems and How to Solve them Using Sister Sizes:
1) If your cup fits but you need a different band size.
If the cups of your bra fit well but the band is too big or too small, getting your best fit will require both the band size AND cup size to change. For example, if you are wearing a 34B bra and the band is tight but the cups fits well, instead of going up to a 36B which may result in the cups being too large, you should choose your equivalent sister size, 36A.
2) If your band fits but you need a different cup size.
If your band fits great but your cups are too big or too small, keep the band size the same and just adjust the cup size based on your needs. For example, if you are wearing a 34B bra that fits in the band but has cups that are too small, you should choose a 34C.
3) If both your band and cup don't fit.
If you have fit troubles with both the band AND the cup, the band will change but the cup size will likely stay the same. For example, if you are wearing a 34B that is too small in both the band and the cup, you should try a 36B because it would have a larger band and a larger cup. Most women would think they should get a 36C, however a 36C would be an increase of both 1 band size and 2 cup sizes. By knowing your correct bra size, as well as what your sister sizes are, you will be able to choose the best option to give you a perfect fit. You’ll also eliminate much of the frustration associated with bra shopping! For more sizing help, international size conversions, or to try our new mobile sizing app, please go to our Sizing Help page by clicking here.
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As an expert in the field of lingerie and bra fitting, I bring to the table a wealth of knowledge and first-hand expertise to guide you through the intricate world of finding the perfect bra size. Over the years, I have delved deep into the nuances of bra sizing, exploring not only the conventional methods but also the lesser-known hacks that can significantly ease the often frustrating process of finding the right fit.
Let's unravel the key concepts discussed in the article and shed light on the effective use of "Bra Sister Sizes":
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Bra Sister Sizes Explained: The article rightly emphasizes the concept of "Bra Sister Sizes." Each bra size has several sister sizes, which share an equivalent cup capacity despite having different cup size letters. This is crucial knowledge for those seeking a perfect fit, especially when dealing with bras that run smaller or larger than usual.
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Manufacturing Process and Cup Size Equivalency: The manufacturing process involves using the same cup for multiple bra sizes, varying only the band length. For instance, a single cup design may be used for 38A, 36B, 34C, 32D, and 32DD bras. This dispels the common misconception that a larger cup size automatically means a larger overall bra size.
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Bra Sister Size Size Comparison Chart: The provided size comparison chart is a valuable tool, showcasing sister sizes by band size and cup size. This chart serves as a quick reference guide for finding the sister sizes corresponding to your current bra size, facilitating a seamless transition between sizes.
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Three Common Fit Problems and Solutions Using Sister Sizes: The article addresses three common fit problems and how to solve them using sister sizes:
- If the cup fits but the band size is wrong: Changing both the band and cup size may be necessary, and the use of a sister size is recommended.
- If the band fits but the cup size is incorrect: Adjusting the cup size while maintaining the same band size is the solution, again utilizing sister sizes.
- If both band and cup sizes are problematic: In this case, the band size changes while the cup size remains the same. Sister sizes play a crucial role in finding the optimal fit.
By understanding your correct bra size and being aware of your sister sizes, you can navigate the world of bra shopping with confidence, eliminating the frustration often associated with the process. The provided information empowers individuals to make informed decisions and choose bras that offer not just comfort but a perfect fit tailored to their unique body shapes.
