Wondering how to measure your bra size?

The phrase one size fits all definitely doesn’t apply to bras. Whatever you think your bra size is, there’s a high chance you’re wrong. Sorry. Just ask any bra fitter, and they’ll tell you that most women walk away with a completely different size than what they’ve been wearing for years. In fact, research by M&S found that 38% of women are unsure if, or know whether, they are wearing the correct bra size.

If, like us, you haven’t bothered to have a professional bra fitting in several years, or are too shy to ask for help from the professionals — after all getting you bra size measured can be quite intimidating — don’t worry, we get it.

While it’s a personal choice whether you wear a bra or not, if you do wear one, you’ll want to ensure it’s right. But before you resign yourself to a life of discomfort or give up on bras completely, we’ve called on the bra fitting experts at Wacoal Europe to break down exactly how to measure yourself for a bra in the comfort of your own home, so you have absolutely no excuse for wearing the wrong size.

First up, why is it important to have a well-fitting bra?

While the wrong size bra may not seem like a big deal, it can cause some real physical problems –but that can be rectified in a few minutes. Bras that are too tight can damage breast tissue and even cause breathing difficulties. Inadequate support can lead to longer term problems such as neck, shoulder and back pain, as well as pinched nerves.

You’re also more likely get longer-term problems like poor posture and premature sagging, which can feel unpleasant. According to experts, with around 4cm range of sway in every direction, very gentle movement while using the wrong bra could be enough to stretch your delicate skin.

Suzanne Pentland, one of Wacoal Europe’s Professional Fit Specialists says a well-fitted bra, whatever the size, should fit snugly around the band, the underwire needs to sit behind all the breast tissue, and sit flush at the centre separating the breasts. The bra cups need to encase all of the breast tissue, and mould to your breast shape with no spillage or creasing in the cup. And this is the case for all bra styles – from push-up bras like the Skims pick above, to backless bras.

How often should you measure your bra size?

Breasts can fluctuate in size and change as often and as drastically as this unpredictable British weather, be that from weight or hormonal changes, particularly during pregnancy, period cycles, contraceptive pills, or menopause. For that reason, you should have a bra fitting every six months to a year to ensure that you are wearing a perfectly fitted bra all year round.

How do you check if you need a new bra?

Fabric stretches, and therefore so do bras, so using an old bra is not an accurate way of measuring your cup size or judging if you need re-measurement. They start to lose shape at around the six months mark as the elastic fibres in the band and straps begin to deteriorate. You may need to start looking into investing in a new bra if you’re seeing the following signs:

1. Your band is riding up your back

A band that’s sitting in the wrong spot, particularly too high, even on the tightest hook, means the bra is stretched out or too loose. Most women make the common mistake of having the band be too large, and the cup too small.

2. Your cups are digging into your breasts

Perhaps one of the most obvious signs is if your breasts are spilling out of the cups and you find yourself seeing “double boobs” in tight-fitting shirts. This means your cups are too small.

3. Your cups gape

Any gaps between your breasts and the bra is not a good sign, even if you’re shifting out of your cups as you move, because this means your cups are too large for your breasts or simply the wrong shape.

4. Your straps keep slipping

If you’ve tried and failed multiple times to tighten your straps but they keep falling off your shoulders, they’ve lost their elasticity.

5. Your bra is showing visible signs of wear

No matter how much you love your bra, if it’s starting to look a little tired (the underwire is poking through or the straps are fraying), it’s time for a new bra.

How to measure your bra size with tape:

All you’ll need is a full-length mirror, a soft tape measure and your top off, although make sure you’re wearing a comfortable but unpadded bra and stand up straight while you’re taking measurements. Here’s how to do it:

1. Measure your band size

Measure (in inches) quite firmly around your ribcage, just below where your bra fits. This will provide your under-band measurement. If the number is odd we advise that you round up to the next even whole number, such as 31.2 to 32.

2. Measure your bust size:

Measure around your back and the fullest part of your breasts, again in inches. Top tip: use your nipples as guidance, making sure the tape is flat against your back but not pulled too tightly. If the total is showing a decimal place like 36.5, go to the nearest whole number.

3. Calculate cup size:

To calculate your cup size, subtract your band size (as referenced in step one) from your bust size (as referenced in step two). Every inch difference is a cup size up e.g. 0 inches =AA; 1=A; 2=B; 3=C; 4=D; 5=DD; 6=E; 7=F; 8=FF  and so on.

Dorling Kindersley

Now before you think that you’re all done, you’re not. While this gives you an approximate bra size, it won’t necessarily be totally accurate. That’s because boobs also vary in shape – which is totally normal, by the way.