US to AU Women's Bras Size Chart
This chart converts women's bras sizes from United States (US) to Australian (AU), covering 41 sizes from US 30A to US 42DDD. Each row shows the direct equivalent so you can find your size at a glance.
Whether you are shopping online from a australian retailer or trying to interpret a foreign size label, this conversion chart gives you the mapping you need. The conversions below follow industry-standard sizing used by major brands, though individual brands may vary slightly.
Quick Converter
| US | AU |
|---|---|
| 30A | 8A |
| 30B | 8B |
| 30C | 8C |
| 30D | 8D |
| 30DD | 8DD |
| 32A | 10A |
| 32B | 10B |
| 32C | 10C |
| 32D | 10D |
| 32DD | 10DD |
| 32DDD | 10E |
| 34A | 12A |
| 34B | 12B |
| 34C | 12C |
| 34D | 12D |
| 34DD | 12DD |
| 34DDD | 12E |
| 36A | 14A |
| 36B | 14B |
| 36C | 14C |
| 36D | 14D |
| 36DD | 14DD |
| 36DDD | 14E |
| 38A | 16A |
| 38B | 16B |
| 38C | 16C |
| 38D | 16D |
| 38DD | 16DD |
| 38DDD | 16E |
| 40A | 18A |
| 40B | 18B |
| 40C | 18C |
| 40D | 18D |
| 40DD | 18DD |
| 40DDD | 18E |
| 42A | 20A |
| 42B | 20B |
| 42C | 20C |
| 42D | 20D |
| 42DD | 20DD |
| 42DDD | 20E |
How to Measure Your Bras Size
Measure your underbust (the ribcage directly below the bust) snugly with a tape measure — this gives the band size. Then measure the fullest part of the bust loosely. The difference between bust and underbust measurements determines your cup size. Each inch (or 2.5 cm) of difference equals one cup letter. Wear a non-padded bra or go braless for the most accurate result.
Understanding US and AU Sizing
The US sizing system is the standard in the United States and is used by most American brands. US sizes are typically numbered and can differ significantly from European or Asian systems. Most US retailers display sizes prominently on labels and online, but the underlying measurements (in inches or centimetres) vary between brands, so treating US sizes as approximate is safest.
Australian (AU) bra sizing follows the same band-number system as UK sizing but uses a different numbering offset — an AU 12, for example, is equivalent to a US 34 or UK 34. Australian sizing is common in Australia and New Zealand. Cup letters (A, B, C, etc.) work the same way as in the UK system.
Tips for Converting Women's Bras Sizes
Australian bra bands use a different numbering system — an AU 12 corresponds to a US/UK 34. Cup letters follow the UK progression.
Australian brands like Berlei and Bonds are popular across Australia and New Zealand. Convert your US band size before shopping these brands.
Bra sizes consist of a band number (underbust measurement) and a cup letter (the difference between bust and underbust). Both must be correct for a good fit.
Sister sizes share the same cup volume at different band lengths — for example, 34C, 36B, and 32D all hold the same breast volume. If your band size is between two numbers, try a sister size in the adjacent band.
Up to 80% of women wear the wrong bra size according to lingerie fitting specialists. Getting professionally fitted or carefully self-measuring can dramatically improve comfort.
Quick Reference
Quick reference: US 30A = AU 8A, US 36D = AU 14D, and US 42DDD = AU 20E. The full chart above covers all 41 sizes in this range.
This women's data is also available in UK, EU, FR sizing. Use the converter tool above to switch between any pair of systems instantly.
Frequently Asked Questions
- How do I convert US women's bras sizes to AU?
- Use our US to AU women's bras size chart above. Find your US size in the left column and read across to find the AU equivalent. For example, US size 36D equals AU size 14D.
- What is US size 36D in AU for women's bras?
- US size 36D in women's bras is equivalent to AU size 14D. This is a standard conversion used across most major brands, though fit can vary slightly between manufacturers.
- Are US and AU women's bras sizes the same?
- No, US and AU use different numbering systems for women's bras. The numbers do not match directly — for example, US 30A corresponds to AU 8A, not AU 30A. Always use a conversion chart rather than assuming the sizes are equivalent.
- What size range does this women's chart cover?
- This chart covers 41 sizes, from US 30A (AU 8A) to US 42DDD (AU 20E). Click any size in the chart for a detailed individual conversion page.
- How accurate are these women's bras size conversions?
- These conversions follow the industry-standard mapping used by major brands and international sizing organisations. However, individual brands may size slightly differently — a US 36D in one brand might fit like a US 36C in another. When possible, check the specific brand's size chart.
- What if I am between two women's bras sizes?
- If you fall between two sizes, the general advice is to size up for comfort, especially for items made from non-stretch fabrics. You can also check whether the brand offers half sizes or fits that run large or small.
- Can I use this chart for all women's brands?
- This chart provides the standard US to AU conversion for women's bras. Most mainstream brands follow this sizing closely, but some brands are known to run large or small. If accuracy is critical — for example, when ordering online with no option to try on — check the brand's own size chart alongside our conversion.