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.
- Why is it important to have a well-fitting bra?
- How often should you measure your bra size?
- How do you check if you need a new bra?
- How to measure your bra size with tape
- How to find your bra size without a measuring tape
- What is a bra sister size?
- How do I know if my bra fits correctly?
- What is the best bra for my boob shape?
- How do I wash my bra?
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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:
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.
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.
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.
If you've tried and failed multiple times to tighten your straps but they keep falling off your shoulders, they've lost their elasticity.
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:
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.
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.
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.
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.
While a tape measure can tell you the right size in terms of numbers, it’s not always the key to finding the perfect fit. The only way to truly get your size spot on is through good old trial and error. Once you have a bra on, you’ll be able to tell if it fits in all the right places, providing the perfect level of support and comfort.
How to find your bra size without a measuring tape
Although measuring your bust size using an actual tape measurer is relatively a pretty accurate way to determine your bra size, there are a few other ways to estimate your bra size if you don't have a measuring tape lying around.
Find a string or ribbon and wrap it around your ribcage, just under your bust. Make sure it's snug but not too tight. Mark where the two ends of the string meet and measure the length with a ruler. This measurement is your band size. Then, wrap the same string around the fullest part of your bust and mark where the ends meet again. Measure the length and subtract your band measurement from it. The difference between the two measurements will give you a rough estimate of your cup size. For example, if your band measurement is 32 inches and your bust measurement is 35 inches, the difference is three inches, corresponding to a C cup.
If you already have a bra that fits well, you can also use its size as a reference. Bear in mind that different brands may have slightly different sizing, so this method may not always yield perfect results. Look at the tag inside the bra and if necessary, use a bra size conversion chart to translate it to a different sizing system.
If you're currently wearing a bra that doesn't fit well, it might be a bit difficult to determine your correct size. However, you can still try and ‘guestimate’ your bra size using it; if your bra is visibly too small or too large in certain areas, it can give you a general idea of what size should fit your bust best. For example, if your cups are overflowing, you may need a larger cup size. Depending on whether your band is riding up your back or is sitting on the looser side, you may need a bigger or smaller band size.
While these methods can give you a rough estimate of your bra size, keep in mind that they may not be as accurate as simply measuring with a soft tape measure. If possible, it's best to get measured by a bra expert at a lingerie store, or simply find yourself a measuring tape to ensure you're getting the most accurate fit.
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What is a bra sister size?
Finding out your bra sister-size is a great hack if you're shopping across different brands or can't find the exact bra size in the style you want. Often women can fit comfortably in their bra size and their sister bra size. Just like clothes, bra sizes are not always universal, and fluctuate from brand to brand, but if you shop around the sister sizes you should be able to easily find your match wherever you decide to shop. Typically, you might choose a sister size when the cups fit but the band doesn’t.
A sister size is essentially the bra size that gives you the same cup volume but with a smaller or larger band size. Some people like a little more wiggle room around the band, while others like it a bit more snug, play around with the your sister size. Although it's worth noting that experts usually recommend keeping the band snug when you first purchase as it's the first part of the bra that will stretch.
How do I know if my bra fits correctly?
| The band | Your under-band provides 80 percent of your bra support, so making sure this fits perfectly is essential. Your band should sit firm and straight across your back on the loosest hook. You should be able to get two fingers at the back of the band but feel a little resistance. If it’s too loose, you need a smaller band size. If you’re struggling to get your fingers in, then you should try the next size up. When buying a bra, make sure your band starts on the loosest hook—this ensures the best support and prolongs the use of the bra as you can tighten the band as it stretches. |
| The straps | The straps are a key part of your bra, they help to balance the weight of the bust. You’ll be forgiven for thinking that the tighter the straps the more support they provide, but straps should actually sit comfortably on the shoulder with space for two fingers underneath without any pinching or sliding. Be sure to check they are equal on both sides. |
| The centre | Also known as the ‘centre gore’, this is the little bit of fabric nestled snuggly between your boobs. It should sit flat to your breast bone without any room underneath but also not digging into your skin. If you can see a gap, you need to go up in size. |
| The wires | If you’re testing out a bra with wiring, be sure to check it fits properly. These should follow the natural curve at the base of your breast round sitting in behind the breast tissue. If they’re cutting in or sitting on it or too far below, they won’t do their job and this is where a large amount of support comes from. |
| The cups | If all the other elements are adjusted correctly, your cups should be smooth and perfectly moulded to the line curve of your breast. Remember the warning signs we mentioned above: spot any wrinkles or sagging? Then move on. Consider the cup capacity; if your cups are too full or breasts are spilling over, it's also time to try another size. |
| The movement test | Raise your arms, bend over, and move around. Your bra should stay in place without the band riding up, straps slipping, or breasts spilling out. Find yourself constantly readjusting? Chances are the fit isn’t quite right. |
And most importantly… Don’t forget to Swoop and Scoop™. You might already be doing it but it is so important as it can completely change how your bra looks, fits and most importantly feels on your body. It’s a quick and easy way to position the underwire, and cups so that your breasts are properly lifted and supported.
How to do it?
| Step 1 | Place one of your hand on your (left) under-band at the bottom of the bra, where the underwire curves at the back. With your opposite hand (right), reach into the top of the cup (left) and move this hand towards the underwire, your fingers should meet. Now, gently bring all of your breast tissue towards the front of the cup with your opposite hand to breast. |
| Step 2 | Repeat on the other breast. |
| Step 3 | If your tissue is ‘spilling’ at the top of your cup, use your index fingers on top of your breasts to smooth it outwards from the centre gore into the cups. |
What is the best bra for my boob shape?
There are a couple of ways to find the right bra for your breast shape. Granted, personal choice is always best – but here are some ways to narrow down your bra selection for maximum comfort and support.
Breasts come in all different shapes and sizes, but experts have narrowed down breast shapes to a number of categories. These include round, east west, side set (widely set), teardrop, narrow, asymmetrical and bell shape. Different bras can comfortably fit different breast shapes – so take note and shop accordingly, (more on that later).
Suzanne says, “A new bra will feel firm but not uncomfortably tight. When a bra fits correctly, the under-band will firmly hold your breasts in place taking 80 percent of the breast weight, and the wire should never sit on your breast tissue. If the wires are uncomfortable, you are likely wearing too small a cup. Also, remember a new bra will always soften after a few washes, making it even more comfortable."
There will be some trial and error involved but here are some bra styles to consider for your breast shape - including picks from the best lingerie brands.
Full and round breasts are equally full at the top and bottom. While most styles work well for this shape (t-shirt bras included), full coverage plunge bras are particularly comfortable and compliment rounder breast shapes well.
Wide-set or side set breasts are shaped with breast tissue laying at the sides, there is often a larger gap between the breasts which exposes more of your chest or ribcage area. For this shape, a plunge bra with a lower centre and a wider band with side support works well.
Teardrop shaped breasts are round, but a little less full at the top. Most underwired styles, such as balconette, full coverage, moulded spacer and padded half cups work well for this shape. Shop some cute wireless bras here.
Asymmetric breasts usually have one breast noticeably bigger than the other – which is very common, by the way. You're better off sizing to the larger breast, and then opting for a side shaper on the smaller side for maximum comfort.
Moulded styles can cleverly conceal the difference in sizing between breasts by providing an even round profile.
For non-moulded styles, look out for stretch elastics stretch lace bras, which are bras that have an elastic panelling along the top and bottom of the bra are a great option for to hug the breast and help them look more even.
Read more: the best bras for big busts and the best bras for small boobs.
Bell shaped breasts usually appear larger and fuller at the bottom, and slimmer at the top. Bell shape breasts are usually found in people who have more breast tissue, so we recommend plunge style bras or a full coverage bra with stretch lace.
How do I wash my bra?
You should wash your bra every three to four wears as a general rule of thumb. Over washing can wear out the fabric, so using a gentle detergent and handwashing or using a mesh, lingerie bag in the machine can help extend its lifespan and protect its shape. Make sure to use the delicate cycle if you're using a machine then lay the bra out to dry instead of using the dryer as high temperatures can cause it lose its elasticity.
**After more bra guides? Shop the best sleep bras, best strapless bras, sticky bras and sports bras. **
