Like many, you may be wondering how to measure your bra size at home. 80% of women are wearing the wrong bra size, but a lot of that has to do with the understanding of bra size and measurement remaining a mystery which is completely unnecessary. We are leveraging our bra expertise to break this all down so you never have to settle for an ill-fitting bra. Our measuring instructions will make it easy for you to find your perfect fit. A visit to our Fitting Room, our advanced online size calculator, can also make sure you find your perfect bra size.
Bra measurements are calculated based on your band size (number) and cup (letter). This is usually determined by measuring around your rib cage, right below your breasts, and your bust at the fullest part of your chest. One item that is often overlooked, and is of the utmost importance, is your breast shape, as it plays a huge factor in your size and what type of bra will be the perfect fit for you.
It’s also important to remember that when you are looking at these measurements to not round to a whole number. ThirdLove makes bras in half-cup sizes so that you don’t have to settle for even a half an inch of discomfort — perfect for those in-betweeners!
Before we begin on how to measure your bra size, it’s essential to gather the right tools. To start with, you’ll need a soft measuring tape. It is essential for accurately wrapping around your body contours.
Secondly, you need a non-padded bra. Wearing a non-padded bra during measurement ensures you get the most accurate representation of your natural breast shape and size, not the result of extra “help” from thick cushiony bras.
To measure your bra band size, you will need to grab a soft measuring tape and wear a non-padded bra. Using your tape measure, stand up and measure your ribcage, right under your bust where your bra band sits. Make sure that the measuring tape is parallel with the ground. The tape should be snug and tight, but not uncomfortable. Make a note of how many inches your under-bust is. Take a look at the chart below and determine your band size based on your under-bust measurement.
To measure your cup size, stand straight with your arms at your side and measure loosely around the fullest part of your bust. This is typically where the nipple is. Make sure the measuring tape is parallel to the ground and not lower or higher in one area. Make a note of your bust measurement.
To get your cup size, subtract your band size from your bust. The remaining number is the over-bust differential and it, along with your band size, determines your cup size. Take a look at the chart below and determine your perfect bra size using your band size and this difference. At ThirdLove, we also offer half cup sizes, so if you're in-between, you don’t need to settle and can get a perfect fitting ½ cup!
Your breast shape, band and cup size rarely fit neatly into a single letter and number. For example, a DD cup size is equivalent to an E cup while a DDD cup size translates to an F cup — but the cup volume depends on the band size. This is where your sister size, or bra size equivalent, comes in which can help you find a better fitting bra.
Sister sizing is when you have the same cup volume and different band size. For instance, if you find that a 34C fits great in the cups, but the band is too tight, you’d need to adjust both your band and cup size to a 36B. Remember: Any time you go up a band size, you need to go down a cup size, and vice versa. Use our helpful Bra Size Chart as a sizing guide.
Women’s breast size can change six times over the course of their lives whether it’s due to pregnancy, weight changes, or other factors. Be sure to always check in to make sure you’re still getting a proper fit and not wearing the wrong bra size.
Here are three easy steps to finding the right bra:
Using our Breast Shape Dictionary, see which category best describes your unique shape.
Identifying common problems, like gaping cups and slipping straps, can determine which size bra you should actually be wearing and whether you need to go up or down a size (or half-cup size).
Different types of bras fit women differently, and are more suited for your lifestyle. Some women prefer a wireless bra while others need more coverage. Some hunt for the perfect T-shirt bra while others feel better in a balconette. Make sure you take the time to consider which style fits you, your life, and your style the best when bra shopping.
Want to find your size, quick? Try our bra size calculator! All you need to do is enter your underbust and bust measurements, and voila, in just a click, we'll calculate your bra size for you!
One thing to remember though is that all breasts are different shapes and have different tissue distribution. Breasts come in different shapes and sizes, and often times, there can be more to your bra fitting experience than a number and a letter. This is why we recommend that you not only calculate your size using our bra size calculator but also take our online Fitting Room Quiz!
Our Fitting Room Quiz does not solely rely on numbers; we consider your breast shape and how that affects your fit, your current bra fit issues (we've all been there), and your comfort preferences. Think of it as a heart-to-heart with your trusted bra expert. With the use of actual human knowledge and our proprietary algorithm, you can rest assured of personalized recommendations for bras that are a perfect fit suiting your style and needs.
Let's explore answers to some of the most common questions that we receive about bras!
Oh, you'll know when it happens! It's like falling in love. When you nail the perfect size, your bra will feel comfortable and supportive; your girls will feel snug yet free—no discomfort, no pain, no irritation, just pure delight. The straps won't dig into your shoulders or slip; the band won't be riding up or sliding down. It will be a beautiful bra harmony that will leave you feeling confident and beautiful.
Absolutely! First for your breast shape, then for the occasion. For example, if you have shallow breasts, you may want to rock a demi or balconette bra for extra oomph. Feeling sassy? A lace bralette can suit the vibe.
First things first, your comfort reigns supreme; more than the numbers and letters, your fit and support matter most. It might depend on knowing how to measure your bra size; that is why we have the Fitting Room Quiz.
Absolutely, all the difference! Whether you end up with sagging or quad-boobing breasts or you will enjoy a comfortable fit and support depends on it. It is not only a matter of fashion but also a matter of self-care.
Still searching for your perfect fit or want help measuring your bra size? Our Fitting Room is an advanced size calculator that has helped millions of women find their perfect size, and you could be next.Many women encounter specific issues during their shopping journey. One common concern is uneven breasts. It’s completely normal to have asymmetrical breasts. When measuring bra size, use the larger breast as your guide. If you desire, you can opt for a style with removable padding to balance out the appearance.
Sometimes, you may try multiple sizes, yet none feels quite right. It might be because you are in between sizes. Try a half-cup size to address the issue.
To ensure you get the most accurate measurements and find your perfect fit, consider measuring twice, both in the morning and the evening. Breast sizes can fluctuate slightly throughout the day. Taking measurements at different times of the day will give you a more comprehensive understanding of your size range. If you find yourself in between sizes, consider your personal comfort preference. If you prefer a snugger fit, go with the smaller size and vice versa.
Beyond measurements and bra size charts, you can take ThirdLove’s Fit Finder Quiz for a personalized recommendation. It does an in-depth assessment that considers your breast shape for the perfect match.
Ready to turn your newfound knowledge into action? Once you’ve found your fit with the bra cup size chart, head over to ThirdLove and find your perfect match among our beautifully crafted bras.
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Returns & exchanges free for 60 days for all orders. Please try on the bra to ensure a good fit, making sure to leave the original tags attached. We only accept underwear in unworn condition, with original tags, in its unopened original polybag. Items marked final sale are not eligible for return or exchange. If something’s not right, we can help. Our Fit Experts are available via live chat, or email to answer any questions you might have.
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Styles in AA-H, including half cups
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