Understanding Australian Bra Sizes

The only things women say they dislike shopping for as much as a new bra are swimwear and jeans. This is such a shame because getting new lingerie should be fun. But with so many variations in Australian bra sizes between brands and styles, it’s a bit like Goldilocks – “just right” can seem elusive. Yet it doesn’t need to be!

It’s really important to wear a correctly fitted bra, and the only way to properly identify the right size and style of bra for you is to be fitted by a certified professional bra fitter. Every woman should be fitted throughout adolescence, early in a pregnancy, post-breastfeeding, and throughout mid- and later life. Changes due to weight gain or loss, hormones, breast surgery, and ageing all impact the size, shape, and weight of the breasts.

Understanding Australian bra sizes is the first step to a more comfortable, functional, and healthy fit.

Australian Breast Size

Bras have been worn around the world in one form or another for many hundreds of years, but it is only since the 1930s that they came to resemble what we recognise and wear today. 

Women’s bodies are changing too, and not only are today’s women bigger overall than they were half a century ago, but our relative breast size is also increasing. Even as recently as the mid-1980s, a D-cup breast was not common at all – but today, it is the norm.

Worldwide, the countries with the largest average breast sizes are Finland, Sweden, Norway and Russia, followed by the USA (all averaging DD cup sizes).  Asian and African nations have the smallest, with predominantly B and A cup sizes being most common. 

Australia is way down the list: in 2020, the most common Australian bra sizes are reported to be 14C and 12D, and while this is the average across all ages, there really is no such thing as the “average” woman. Two women may look similar in size and shape, yet be two very different bra sizes – and one woman may even have perfectly-fitted bras of different sizes in her lingerie drawer.

Understanding Australian Bra Sizes

Understanding both Australian bra bra sizes and international bra sizing can be overwhelming, with seemingly complex numbers and lettering systems. 

There are two major factors in bra sizing:

1. Band Size: this “underbust” or frame measurement is denoted as a number, and measures the body underneath the breasts. Australian bra sizes typically range for band sizes from 8 (25-27 inches) to 26 (43-45 inches).

2. Cup Size: this is the “overbust” measurement, around the body at the fullest part of the breast.  In Australia, this is represented by a letter, ranging from A to H. 

The cup size for an 8A bra is smaller than for a 14A bra; cup sizes are created relative to the band size.

The Issues with an Ill-Fitting Bra

A poorly-fitted or incorrect bra will not only feel uncomfortable and make you look unsupported; it can create an array of health problems.

• Wearing an unsupportive bra can result in breast pain, as well as neck, shoulder, and back pain.
• An ill-fitting bra can cause skin irritation and chafing.
• A poorly-fitted sports bra can deter a woman from exercising. Lack of support may cause damage to the breast tissues during exercise.
• A bra that is too tight may impede proper lymphatic drainage and restrict blood circulation, compromising the removal of toxins from the breasts and potentially leading to major health problems over time.

How to Measure Your Bra Size

1. Measure your chest around your ribcage and directly underneath your breasts where the lowest part of your bra sits. Hold the tape measure snug but not tight. This measurement gives the band measurement. Record this in inches. (Note 1 inch = 2.5cm).
2. Measure around your body at the fullest part of your breasts. This will often (but always) be over the nipples. Record this in inches.
3. Round both of these measurements up to the nearest inch.
4. Subtract the underbust measurement (inches) from the overbust measurement (inches).
5. Determine your bra size:
   1. If your underbust measurement is under 33 inches, add 5 inches. e.g. 30 inches plus 5 inches = 35 inches. This is your band size. (if your underbust measurement is over 33 inches, add only 3 inches).
   2. Look at the difference in inches between your original underbust measurement and your overbust measurement. Your cup size should correspond to the following measurement over band size in inches:
      
      +1 = A
      +2 = B
      +3 = C
      +4 = D
      +5 = DD or E
      +6 = DDD or F
      +7 = G
      +8 = H

Note that bras do not tend to come in half sizes (i.e. odd number band measurements). If you measure and add 5 or 3 inches as described in step 5.i above, and you get an odd number, you can either go down by an inch and up a cup size, or up an inch and down a cup size. Essentially, a 12D bra will fit the same size as a 14C.

International size conversions need to be understood too, for example:

Bra Fitting vs Measuring

While the above measurement method using the international and Australian bra sizes should give you your correct size, measuring alone does not account for differences in bra style and design and body shape. Cup style, feel, fit, straps, wires, centre, and other factors all combine to determine the perfect bra for you.

This is why you need to be fitted professionally!

Choose CasaMia for Professional Bra Fitting

CasaMia is the leading Bra Fitting and Mastectomy specialist boutique in the Illawarra, offering exquisite women’s lingerie, including plus size lingerie, sports bras, maternity and post-surgery bras (including mastectomy bras, swimwear, and a prosthesis-fitting service).

Maralyn is an expert, trained and certified professional bra fitter with many years of experience fitting the right bras for women of all sizes and stages of life, and can help you understand Australian bra sizes and find a perfect fit for your body.. Her care for her customers and her insight are second to none.

Visit CasaMia Lingerie

Browse our collection of bras and sports bras now to shop online, or visit us instore at Warilla or Fairy Meadow for a specialised fitting or advice.