How to Measure Your Bra Size at Home: A Complete Guide

Finding the right bra size is the foundation of comfort and confidence. Studies suggest that up to 80% of women wear the wrong bra size, often without realising it. The good news is that measuring your bra size at home is straightforward once you know the correct technique. This comprehensive guide will walk you through the professional method used by certified bra fitters.

What You Will Need

Before you begin, gather a soft measuring tape (the kind used for sewing), a mirror, and optionally a non-padded bra that fits reasonably well. Avoid using a metal or retractable tape measure, as these can be inaccurate for body measurements and uncomfortable against your skin.

💡

Best Time to Measure

Measure yourself at a time when your breasts are at their usual size. Avoid measuring right before your period when hormonal changes may cause temporary swelling. Mid-cycle typically provides the most consistent measurements.

Step 1: Measure Your Band Size

The band provides approximately 80% of a bra's support, making this measurement crucial. Stand in front of a mirror and wrap the measuring tape snugly around your ribcage, directly under your bust where the band would sit. Keep the tape parallel to the floor all the way around your body. The tape should be firm but not tight—you should be able to fit one finger underneath comfortably.

Take note of this measurement in centimetres or inches. If you measure in centimetres, you will need to convert to the standard Australian sizing. For band sizes, round to the nearest even number. For example, if you measure 73 centimetres, you would typically wear a size 10 band; 78 centimetres corresponds to a size 12, and so on.

Step 2: Measure Your Bust

Now wrap the measuring tape around the fullest part of your bust, typically at nipple level. Keep the tape parallel to the floor and ensure it sits comfortably without compressing your breast tissue. This measurement should be looser than your band measurement—do not pull the tape tightly.

Stand naturally with your arms relaxed at your sides. Looking straight ahead into the mirror, check that the tape has not ridden up or down at the back. An uneven tape will result in an inaccurate measurement.

⚠️

Common Mistake

Bending forward during measurement can distort your results. Stand upright with good posture for the most accurate reading. If you have difficulty keeping the tape level by yourself, ask someone to help.

Step 3: Calculate Your Cup Size

Your cup size is determined by the difference between your bust measurement and your band measurement. Each 2.5 centimetres (or 1 inch) of difference corresponds to one cup size. Here is a general guide for Australian sizing:

Less than 2.5 cm difference: AA cup
2.5 cm difference: A cup
5 cm difference: B cup
7.5 cm difference: C cup
10 cm difference: D cup
12.5 cm difference: DD cup
15 cm difference: E cup
17.5 cm difference: F cup

Understanding Sister Sizes

Sister sizes are an invaluable concept that every woman should understand. If your usual size is not available or does not fit quite right, sister sizes offer alternatives with the same cup volume but different band lengths. For example, if you wear a 12C, your sister sizes would be 10D (smaller band, larger cup letter) or 14B (larger band, smaller cup letter).

This knowledge is particularly useful when shopping across different brands, as sizing can vary. If a bra feels too tight in the band but the cups fit well, try your sister size with the larger band. Conversely, if the band rides up and the cups gap, try the sister size with the smaller band.

🎯

Key Takeaway

Your bra size is not a fixed number. It can change due to weight fluctuations, hormonal changes, pregnancy, and ageing. Re-measure yourself every six to twelve months, and whenever you notice changes in how your bras fit.

When to Seek Professional Fitting

While home measurements are a great starting point, some situations benefit from professional assistance. If you have a significant difference between breast sizes, unusual breast shapes, or have undergone surgery, a professional fitter can provide personalised advice. Many Australian department stores offer free fitting services.

Professional fitters are trained to identify subtle fit issues that may be difficult to detect yourself. They can also recommend specific styles that work best for your unique shape and preferences. Do not hesitate to seek professional guidance, especially for special occasions or if you have been experiencing ongoing discomfort.

Final Thoughts

Measuring your bra size at home is a skill that empowers you to make informed purchasing decisions. Remember that the numbers are merely a starting point—the true test is how a bra feels when you wear it. A well-fitting bra should feel comfortable from the moment you put it on, with no adjustments needed throughout the day.

Take your time with the measuring process, and do not be discouraged if your first measurement seems unexpected. Bra sizing is not intuitive, and many women are surprised to discover their true size. Trust the process, and remember that comfort is always the ultimate goal.