The fitting room experience isn't for everyone. Between the lighting, the waiting and the awkwardness of being measured by a stranger, it's no surprise that most women either guess their size or stick with whatever they were told years ago. The good news is you don't need a fitting room or a professional fitter to find your correct bra size. All you need is a soft tape measure, a non-padded bra, and about two minutes. Here's exactly how to do it.

What You'll Need

• A soft measuring tape — the flexible kind used for sewing, not a metal builder's tape
• A non-padded, well-fitting bra — or no bra at all for the most accurate measurement
• A mirror — to check the tape is sitting level
• A pen and paper — to note your measurements

Measure in centimetres if possible — Australian bra sizing uses centimetres for band measurement. If your tape only shows inches, multiply by 2.54 to convert.

Step 1 — Measure Your Band Size

Converting to your band size:

If your measurement falls between two sizes, try both — your body and the bra style will tell you which feels right. Generally, if you're between sizes, size down for a firmer band if you prefer more support, or size up for a more relaxed fit.

Step 2 — Measure Your Bust

Step 3 — Calculate Your Cup Size

Subtract your band measurement from your bust measurement. The difference gives you your cup size.

So if your band measures 75cm (size 14) and your bust measures 88cm, the difference is 13cm — which puts you in an F cup. Your starting size would be a 14F.

Understanding Sister Sizing

Sister sizing is one of the most useful concepts in bra fitting — and one of the least known. Your "sister sizes" are bras with a different band and cup combination that contain the same volume of fabric in the cup. This matters because if a bra fits in the cup but the band is too loose or too tight, you can adjust both simultaneously without losing the cup fit.

How sister sizing works:

• If the band is too tight — go up one band size and down one cup size (e.g. 14F → 16E)
• If the band is too loose — go down one band size and up one cup size (e.g. 14F → 12FF)

The cup volume stays essentially the same — only the band tightness changes. This is particularly useful when shopping online or when your preferred size isn't available in a particular style.

How to Check the Fit Once You Have Your Size

Your measurements give you a starting point — but the real test is how the bra feels on your body. Here's what to check:

• Band: Should sit firm and level all the way around — not riding up at the back. You should be able to fit two fingers underneath, no more.
• Cups: Should contain the breast completely with no spillage over the top or sides, and no gaping or wrinkling.
• Centre gore: The piece of fabric between the cups should sit flat against your sternum — not floating away from your body.
• Straps: Should sit comfortably on your shoulders without digging in or falling off. You should be able to slide two fingers underneath.
• Overall: A well-fitting bra should feel comfortable from the very first wear — no breaking in required.

Why Your Size Differs Between Brands

Once you have your measurements, it's important to know that bra sizing is not standardised across brands. A 14F in Elomi may fit differently to a 14F in Freya or Berlei — because each brand has its own cup shape, wire placement and band construction. Your measurements give you the best starting point, but always be open to going up or down a size when trying something new.

This is especially true when moving between brands for the first time — the key is to use your measurements as a guide and let how the bra actually feels on your body be the final word.

Frequently Asked Questions