Bra Size Calculator, Bra Size Converter & Conversion Chart
Measuring Bra Sizes, Bra Size Charts & Calculators
What’s My Cup Size?
This is a question many women struggle with throughout their life. An estimated 75 to 80% of modern women wear bras that don’t fit them correctly on an everyday basis. Wearing a well-fitting bra is key to avoiding daily discomfort, keeping your breasts secure, preventing chronic pain, and lifting and shaping your bust. Therefore, whether or not your bra fits you well has a significant impact on your daily comfort, appearance, and even long-term physical health. With that in mind, it’s shocking that the vast majority of women wear ill-fitting bras every single day.
Statistically speaking, it’s more likely than not that the bra size you wear is not actually the size that fits you best. Bra sizing is complicated, so determining whether or not a bra fits you correctly tends to be much more difficult than it seems. Plus, your bra cup size varies depending on the brand of the bra, the sizing system it uses, and how your body changes over time. Every woman should know how to measure their own bra size accurately so they’re never left wondering about what their ideal cup size is and whether or not they’re wearing the right one.
Measuring Bra Size
Many different factors are involved in determining your ideal bra size, which can make measuring yourself to figure out your bra size very complicated. However, learning how to measure your own bra size at home with as much accuracy as possible gives you the power to make sure every bra you buy and wear fits you well.
It is unwise to rely on the sizes that employee fitters at lingerie shops and department stores assign you. While these recommendations can definitely point you in the right direction, you should treat them as a rough estimate rather than fact. Most professional fitters just hastily measure your bust over your shirt and current bra, resulting in measurements that are significantly skewed. You’ll end up with a much more accurate idea of your own bra size if you measure it yourself from the comfort of your own home.
Bust Size vs. Bra Size
It’s easy to get confused over the difference between your bust size and your bra size. After all, the purpose of bras is to fit, support, and secure your bust. However, the size of your bust is not the only thing you need to consider
In reality, your bust size is just one factor that influences your ideal bra size. The size of your bust determines what your bra cup size is and what cup letter you should wear, but a well-fitting bra fits your body as a whole. Basing your bra size entirely off of your bust size is a common mistake that results in many women wearing bras that don’t fit them correctly. It’s important to learn about all the various factors and measurements that impact your bra size in order to make a well-informed, accurate decision the next time you go bra shopping.
How to Measure Bra Band Size
Measuring your band size correctly is key if you want to end up with a bra that fits comfortably and offers enough support and security for your best. The band of your bra is responsible for supplying the majority of the support your bra provides. If it fits too loosely, it won’t be able to offer enough support, which can lead to bouncing, discomfort, and long-term sagging.
Use a floppy measuring tape to measure the circumference of the area directly under your bust—where the band of your bra should rest. Hold the tape snugly but comfortably against your skin. Holding it too loosely or too tightly will result in an incorrect measurement. Add four to the the number of inches you measure if the number is even—and five if the number is odd—to get your correct band size.
How to Measure Bra Cup Size
Your bra cup size is a combination between your bust size and your band size. Always measure your band size before measuring your cup size so that you know your band measurement and can compare it to your bust measurement to determine your ideal cup letter.
Measure around the widest part of your bust—usually across the center of your nipples —using a soft measuring tape. Subtract this number from your band size. This difference corresponds to your cup letter. In the US sizing system, a one-inch difference is an A cup, two inches is a B cup, three inches is a C cup, four inches is a D cup, etc. Remember to calculate the difference between your bust measurement and band measurement using your rounded-up band measurement, which is not necessarily the same number as your initial measurement.
Bra Size Charts
Bra size charts are a measurement tool that lays out the basics of bra sizes and how they correspond to certain band and bust measurements. They organize bust and band measurements into a comprehensive chart that matches these measurements with bra cup letters and band sizes. These charts can be an extremely helpful resource for at home-bra measuring.
You can find bra size charts for most common international sizing systems, including the US, UK, and EU systems. You can also find bra size charts for sister sizes—bra sizes that are equivalent in cup volume but differ in cup letter and band size—which can help you determine which sizes to try if your measurements are in between sizes.
Bra Size Calculators
Bra size calculators are another valuable tool that can help you determine your ideal bra size based on your at-home measurements. These calculators allow you to enter your bust measurement and band measurement separately and assign you a bra size according to your entries. This saves you from the confusion of having to manipulate your raw measurements to calculate your ideal bra size by hand.
If you’re shopping online for a new bra, always check if the online shop offers a bra calculator. Many online lingerie stores provide a bra size calculator that assigns you a size that is specific to the brands they sell. Even if you know your normal bra size, input your measurements into a bra size calculator whenever possible to make sure your size matches up with the sizing of the bra you’re considering buying.
Bra Size Calculator US vs. Bra Size Calculator UK
Bra size calculators are an especially helpful resource when it comes to calculating your bra size in a sizing system that is unfamiliar to you. The US and UK bra sizing systems have subtle but significant differences between them. These two systems are two of the most commonly used sizing systems among mainstream lingerie brands, so you’re likely to come across both of them at some point throughout your bra shopping endeavors regardless of which part of the world you live in.
There are some important differences between using a US bra size calculators versus using a UK bra size calculator. US bra size calculators generally ask you to enter your measurements for bra cup sizes in inches, while UK calculators accept data for bra cup sizes in centimeters. However, some more advanced bra size calculators—which are for free use online—allow you to decide whether or not you want to input your data in inches or centimeters as well as choose which sizing system you want your bra size to match.
How to Find the Perfect Bra for You
1. Remeasure Regularly
Few things are guaranteed in life, but you can pretty much count on the fact that your bra size will not stay exactly the same throughout your entire adult life. If you’ve been wearing the same bra size on autopilot for more than several years, it’s very likely that the size you’re wearing is incorrect even if it was once the ideal size for you.
It’s a good idea to remeasure your bust every time you’re considering buying a new bra. This might seem excessive, but your bust size changes significantly in response to even the most subtle shifts in your body composition. Losing five pounds or taking up light weight-lifting at the gym can cause your cup size to change by a full letter. Larger changes in your body, like major weight loss, pregnancy, or menopause usually result in even more drastic shifts in size.
Since your body changes gradually, you probably won’t even notice if the bra size you’re used to wearing becomes less accurate over time. Wearing an ill-fitting bra still causes you to receive inadequate support and leads to discomfort regardless of whether or not you notice your bra size has changed, which is why it’s so important to confirm your size before you buy a new bra.
2. Recognize Red Flags
Measuring your bra size correctly is important, but it doesn’t guarantee that every bra in that size will be your perfect fit. Some bras follow a skewed sizing system, or are just poorly designed and won’t fit you correctly even if they’re labeled with your size. Learning to recognize the red flags of a hopelessly ill-fitting bra can cut uncertainty out of your bra shopping process and prevent you from accidentally buying an uncomfortable bra that lacks the support and security you need.
The first things you should keep your eye out for when you try on a bra are gapping or wrinkled cups. If your bra cups don’t lay flat against your skin or wrinkle, that means the cups are too large and your bust isn’t adequately filling them. On the other hand, if the cups of a bra are digging into your skin, that’s a clear sign that you need to go up a cup size.
The straps of a bra are a useful indicator of how well the band is supporting your bust. If the straps of a bra slip down over your shoulders or dent your skin, that means that the band of the bra is either too loose or too tight and is forcing the straps to pick up its slack in terms of support. Also, a bra’s band riding up or digging into your skin are also signs that it is too large or too small for you. Your band should stay securely in place and its center—the part in between the cups—should lay flat against your chest at all times. Test the fit of a bra’s band by lifting your arms up over your head when you try it on. If the band rides up at all, it doesn’t fit you correctly.
Any new bra you buy should always fit you best when fastened on the loosest clasp. Bras stretch out naturally over time, so any bra that only fits you when you fasten it on the tightest clasp from the get-go will likely only end up fitting you for a very short period of time.
3. Dress for Success
Have you ever tried on a bra in a store, loved it and brought it home, and then ended up hating the way it looks underneath every piece of clothing you own? This frustrating phenomenon is much more common than it should be, but it’s completely preventable. Bras tend to look very different when you wear them alone versus when you wear them under a top; just because a bra fits when you try it on by itself does not mean it will still look good after you get dressed. Always try on a bra underneath a top before you make a purchase to determine whether or not a certain bra fits well when you’re actually wearing clothes.
A form-fitting—but not overly tight—T-shirt is one of the best test tops to wear when you go bra shopping. T-shirts are one of the most difficult tops to pair with a bra. The thin, form-fitting fabric of standard tees tends to reveal bulges, gapping, seams, and dreaded quad-boob much more clearly than other top styles. After all, one of the most popular bra styles—T-shirt bras—are designed specifically to maintain a smooth, invisible finish underneath your T-shirts. If a bra you try on still looks good and fits well when you wear it under a T-shirt, chances are it will work well with almost any other top you own.
4. Buy in Bulk
Finding a well-fitting, high-quality bra you truly love is akin to finding a pot of gold at the end of a rainbow. If you find a bra that is comfortable, supportive, attractive, and fits you well, consider buying more than one. The fit of different bra styles varies depending on their materials, design, and the quality of their construction. Loving a bra style in a certain size from one brand doesn’t mean that you’ll love a similar style in the same size from a different brand. Plus, there’s no guarantee that a certain brand will continue selling your favorite bra style indefinitely.
Buying more than one copy of your favorite everyday bra style gives you insurance against the frustration of changing inventory options, but you shouldn’t buy more than three identical bras. Within a few years, your bra size will probably change slightly, rendering a never-ending collection of one bra style in one size a useless waste of money. Only purchase two or three copies of the same bra at a time, and remeasure yourself before buying again.
5. Don’t Be Afraid of Online Shopping
As long as you know how to measure your own bra size correctly from home and recognize the red flags of an ill-fitting bra, you should be able to find just as much success with bras you buy online as with bras you find in brick-and-mortar lingerie and department stores. While you shouldn’t be afraid to buy bras online, you should still exercise a good amount of caution when determining whether or not to make a purchase from a certain online shop.
Always review the bra size charts on an online store before you buy a bra from that website. Make sure that you measure your bust according to the sizing system the store uses. Never assume that a certain store uses a US sizing system just because they’re a US-owned company—many US-owned online stores carry bras that are made by international manufacturers and conform to a different sizing system.
Also, check reviews whenever possible to get a better idea of both the quality of the bra you’re considering as well as the reputation of an online store itself. If a certain online shop doesn’t list reviews on its products and you can’t find much information about it through online searches, that’s a good sign that you’ll probably have more success shopping elsewhere. There are plenty of honest, reputable online lingerie stores that sell real, high-quality bras, so you should never settle for buying from a sketchy, little- known retailer.
Bra Size Chart, Bra Cup Size Calculator, European Bra Sizes and US Bra Sizes