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Article: Bra Sizing: Understanding The Complexity

Woman sitting on floor in lingerie with Bra Sizing in the background

Bra Sizing: Understanding The Complexity

When it comes to the realm of women's clothing, few items are as essential and complex as the bra. Beyond the aesthetic appeal, bras serve the crucial function of supporting and shaping a woman's breasts. However, with numerous sizes, styles, and fits available, the quest for the perfect bra can often seem daunting. Let's delve into the intricacies of bra fittings, sizes, and why finding the right fit is so pivotal.


Decoding AU Bra Sizes: More Than Just Numbers

Bra Cup and Band size InfographicBras are labeled with an alphanumeric combination containing a band and cup size, such as 12C. The number, in this case, 12, denotes the measurement around the torso directly beneath the breasts - this is known as the band size. On the other hand, the letter C represents the cup size, indicating the volume required to accommodate the breasts.

Cup Sizing: In Australia, the bra size spectrum spans from AA to K. The cup sizes in the Australian system progress in a specific sequence, starting with AA and then advancing through A, B, C, D, DD, E, F, FF, G, GG, H, HH, J, JJ, and culminating with K. Concurrently, the band sizes follow a pattern, increasing in increments of two.

Band Sizing: The band size progresses in increments of two, such as 6, 8, 10, 12, and so on up to a 34. Each of these sizes correlates with a specific under-bust measurement range, like 68-72cm for size 10 and 73-77cm for size 12, and so on. It's worth noting that your dress size doesn't always match your bra band size.

Converting Bra Sizes: In regions that follow the European EN 13402 dress-size standard, measurements tend to be rounded to the nearest multiple of 5 centimeters, such as 70, 75, 80, and so on. Comparatively, countries that haven't adopted this standard such as the US increment in units on 2, rounding down to the nearest 2 inches then adding 4. Navigating between sizes can indeed be a bit perplexing! If you find yourself in need of some clarity, feel free to consult our international size guide for assistance!


The Relationship Between Band & Cup Sizes

Bra cup size increasing with band size

It's crucial to understand that the cup size is not static and varies based on the band size. For instance, a D cup on a 16 band holds more volume than a D cup on a 12 band. This nuanced relationship reflects the changing proportions of a woman's body as her chest band dimension increases.

Understanding the relationship between band and cup sizes is pivotal, particularly when considering sister sizing. Sister sizing means that as the band size goes up, the cup size adjusts to maintain the same volume. For instance, if someone typically wears a 12D, they might find a 14C or 16B to have a similar volume when size availability is limited.


The Complexity of Women's Anatomy

Infographic of womens breasts

While bra designs aim for an "ideal" body shape, women's anatomies are incredibly diverse. Factors like asymmetry, where one breast may be larger than the other, are prevalent—studies suggest that the left breast is larger in 62% of such cases. Additionally, variations in breast shape, spacing, and fullness further complicate the fitting process.

Consequently, finding a bra that fits perfectly is a formidable challenge. Interestingly, when women do stumble upon a seemingly fitting bra, they often cling to that size, even if their body undergoes changes due to weight fluctuations or other factors.


Signs of an Ill-fitted Bra

bad fitting bra vs good fitting bra comparison

Recognising signs of a well-fitted bra involves observing several factors. A bra band that rides up the back indicates a loose fit, whereas flesh spilling over the edges signifies a size too small. Experts advise women to opt for the outermost set of hooks initially, ensuring the ability to tighten the bra as it inevitably stretches over time. If you have been wearing your bra for over 6 months, it is also likely that it has stretched. Opting to purchase the same size of a stretched bra may result in a tight and uncomfortable fit which is why it is best practice to visit a bra fitter each time you need to stock up. 

Problems that may arise from an ill-fitting bra:

  • Bad posture

  • Straps digging in

  • Headaches

  • Premature sagging

  • Neck and shoulder pain

  • Slipping straps

  • and more!

If you have any of the above issues, investing some time into a professional fitting could help relieve these issues. 

Hint: If you’re not comfortable in your bra, then you’re likely not wearing the right size and/or style for your body shape.


The Importance of Professional Bra Fittings

Bra fitter adjusting customers bra strap

Despite the challenges, the significance of a well-fitted bra cannot be overstated, particularly for larger cup sizes D and above, after significant weight fluctuations, and during pregnancy. With women on average changing their bra size six times throughout their lifetimes, it’s crucial to regularly visit a bra fitting expert for a hassle free bra wearing experience.

The best bra fitting will be one where your fitter takes all the hard work from finding your size and you leave feeling comfortable, supported and proud of your figure. When looking for a fitter, it’s important to find someone that has years of experience and has knowledge of a wide range of products and lingerie brands. You’ll find that you’ll generally also receive more specialised service and expertise from small lingerie boutiques compared to large department stores.


Your Bra Size isn’t the be-all and end-all

While pinpointing your exact bra size serves as a useful starting point, it's essential to recognise that this metric isn't the definitive answer to all fitting dilemmas. The world of lingerie is filled with variations; each brand, style, and even colour variation can introduce subtle differences in fit and comfort. Therefore, it's entirely common for individuals to exit a bra store with an assortment of sizes in hand. Factors such as fabric stretch, design intricacies, and manufacturing nuances contribute to these discrepancies. It’s important to prioritise comfort and support over sticking to a singular size. In essence, while understanding your general size is beneficial, remaining flexible and receptive to variations ensures a tailored fit that aligns with your individual preferences.


While the journey to finding the perfect bra may seem like a labyrinth, understanding sizes, considering professional fittings, and acknowledging the dynamic nature of women's bodies are pivotal steps toward achieving comfort, support, and confidence in every attire. After all, a well-fitted bra does more than enhance appearance—it empowers women to embrace their unique shapes and sizes with grace and comfort.

About The Author
Lingerie Specialist
Famously known throughout Moonee Ponds and Greater Melbourne as the "Bra Fairy", Tracey has been helping women feel comfortable and confident through stress-free bra fittings for over 38 years.

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