Bra sizes how to calculate

How to Measure Your Bra Size

This article was co-authored by Kpoene Kofi-Bruce. Kpoene Kofi-Bruce is a tailor, couture wedding gown designer, and the Creative Director of Mignonette Bridal and Ette the Wedding Tailor in Chicago, Illinois. With nearly two decades of experience as a wedding gown designer, small business owner, and vintage sewing enthusiast, Kpoene specializes in wedding gown design and the social history of wedding dresses. She received a BA in Creative Writing from Middlebury College and studied the business of fashion at the Fashion Institute of Technology. She is also a graduate of the Goldman Sachs 10KSB program and the Chicago Fashion Incubator and has written about wedding fashion for Jezebel, Catalyst, the Sun Times, and XO Jane.

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Believe it or not, at least 80% of women wear an incorrectly sized bra! Most people wear a bra too large in the back and too small in the cups. Although sizing can vary slightly between brands, all follow a basic measurement system that you can use to measure your bra size in the comfort of your own home.

Bra Size Calculator

This calculator estimates bra size based on bust size and band size (frame size). To ensure accuracy, measure to the nearest ¼ inch or ½ cm. This calculator provides results for the United States, the United Kingdom, European Union, France, Belgium, Spain, Australia, and New Zealand.

The bust size is the loose circumference measured around the chest over the fullest part of the breasts, while standing straight with arms to the side, and wearing a properly fitted bra.

The band or frame size is the firm circumference, fitted not tightly, measured directly underneath the breasts.

Bra Size Converter

Use the following to convert the bra sizes between different locations.

Incorrect bra fit

Surveys and studies often cite that anywhere between 70-85% of women wear incorrectly fitted bras. While data collection methods between various sources is not consistent and these percentages may be inflated, incorrectly fitted bras are nonetheless a significant issue, evidenced by the number of studies, articles, and complaints surrounding the issues women face due to a lack of size standardization. Studies have revealed that the most common mistake made by women when selecting a bra was to choose too large a back band and too small a cup. Part of the issue is the lack of standardization regarding band and cup sizes. These vary largely between countries, and even manufacturers, making it difficult to use these measures as anything more than an approximate fit. A 34B bra from two different companies, for example, may not fit the same person because of this lack of standardization.

Some signs of incorrectly fitted bras include the band digging into the torso or sliding upwards, red marks, shoulder or neck pain, the breasts overflowing around the edges of the bra, and the bra’s center panel not lying flat against the breast, among others.

Bra size

The two major aspects of bra size are the band size and the cup size.

Band size (frame size)

The band size is the size of the bra band around the torso. However, band sizes come in different measurements in different countries, in that sizes such as small, medium, and large, equate to different measurements. Refer to the table below for some size measurements, though some variation from the published measurements is possible.

The cup size can be calculated using the difference between bust size and band size. Refer to the table below.

Bra size chart

The size of bras

Brafitting in other words, a perfect fit bra not only in terms of size, but also the right model. Remember that each bust is different, and the fact that we have the same size as a friend, does not guarantee that the same bra model will be just as good for both of us.

It is known that men would prefer women without bras. Unfortunately, like every day, a women’s group must set up the necessary bra for work, office, city or for another occasion. Therefore, it’s time to help women choose the right bra.

How to choose the size of a bra?

How to calculate the size of the bra cup?

How to calculate the size under the bust?

Size under the bust is not the same as the circumference in centimeters! To calculate the size, do the following:

How to establish your bra size?

Bras are one of the key items of underwear for women. They are worn on everyday basis for prolonged periods of time, which means that their size has to be properly adjusted to the preferences of a particular customer. As bra sizes are numerous nowadays, it is sometimes a wise idea to opt for a bra size calculator developed by experts knowledgeable in the field. However, it is still recommended to be aware of what measurements to take and what data to obtain in order to be sure that our cup size in cm is valid and can be later on juxtaposed with a data set available in a brick-and-mortar shop or in its online alternative.

To make sure that the measurements taken are correct and can be typed in into a bra size calculator, you have to make sure that you stand in an upright position with your bra on. In said position, take measurements around your back and under your bust while at the same time remembering that a comfortable bra size should be neither too tight nor too loose.

Cup size in cm can also be a great starting point to establishing your exact size in the letter-based standard, in the case of which, band size has to be subtracted from the bust measurement in order to get codes from AA up to K. If you happen to have certain difficulties doing it on your own, you can always ask a friend or the representative of a given shop for help. Especially in the second case, you can count on professionalism, support, and full understanding of the problem you have been dealing with for quite some time.

How to measure your bust area?

To specify your cup size in cm, you frequently do not need a highly professional bra size calculator. In the majority of cases, all it takes is to use a measuring tape to take measurements around your back and under your bust. Afterwards, write down the pieces of information specified above or memorize them. It will surely make browsing through the available bra sizes much more comfortable and pleasant. The measurements taken are the most important issue, as sizes specified in the letter-based format may vary from producer to producer, so relying on them entirely may not be a sensible idea, especially in this day and age. The selection can be much easier if you just know your personal measurements and are capable of providing them to the representative of a given shop from memory. If you are afraid that you will forget them, take a note with you or leave it next to your desk while making a decision to purchase a bra online. It will save you a lot of hassle and will notably help you make the right, highly satisfactory purchase-oriented decision.

Cup size

What is the result of subtraction? The circumference in the bust minus the circumference under the bust equals the subtraction result and the selection of the correct bra cup.

Bra size

Bra size conversion chart

Remember: measurements are not everything!

The size that we obtain by subtraction or using a calculator or tape is only preliminary. It often happens that two people of identical size should wear bras in two different sizes. Much also depends on the shape and condition of the breast, as well as on individual differences in body structure.

For example: ladies with spherical busts will most likely have to choose a slightly larger bowl than the one received in the table, and for ladies with cone busts, smaller cups will probably fit than it would appear in the table.

A multitude of sizes and types of bras can give you a headache. Starting from bras for everyday use, through immobilizing sports bras, ending with breast enhancement push-up bras.

How do you know that the bra is badly chosen?

The clasp at the back of the bra floats up.

The back of the bra should be arranged in a straight line under the blades. If the clasp of our bra is rising, it means that most of the weight of the breast is based on the straps, and the circumference of our bra is too large.

The bra’s circumference is tight.

If we can not move freely or deeply breathe in the bra, we should increase the size of its circumference.

Breasts do not fill the cups.

The breasts should not fall into the bra inertly and create an empty space in the top of the bowl. It’s worth reducing its size.

Bra sizes how to calculate

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M&S BraFit™

For happy boobs

BRA SIZE CALCULATOR

Measure yourself

Find your size

Book an in-store appointment

Visit us in person and enjoy a one-to-one appointment with an expert bra fitter. We also offer specialist fittings for first bras, nursing bras or post-surgery bras in selected stores

Book a free fitting

Book an in-store appointment

Visit us in person and enjoy a one-to-one appointment with an expert bra fitter. We also offer specialist fittings for first bras, nursing bras or post-surgery bras in selected stores

Book a free fitting

On-demand video call

Want help fast? No problem. Our expert team is here to help you find your perfect bra via a live two-way video call. All you need is your own tape measure

Video call us now

On-demand video call

Want help fast? No problem. Our expert team is here to help you find your perfect bra via a live two-way video call. All you need is your own tape measure

Video call us now

Book your online appointment

Pre-book an online appointment for a time that suits you and get fitted in the comfort and privacy of your home. All you need is your own tape measure

Book a free online fitting

Book your online appointment

Pre-book an online appointment for a time that suits you and get fitted in the comfort and privacy of your home. All you need is your own tape measure

Book a free online fitting

FREQUENTLY ASKED QUESTIONS

Why should I have a bra fitting?

Even if you think you know your size, it’s a good idea to get fitted regularly. The shape of your breasts change with age, when you gain or lose weight, and did you know that you can go up four cup sizes during pregnancy?

Even if you think you know your size, it’s a good idea to get fitted regularly. The shape of your breasts change with age, when you gain or lose weight, and did you know that you can go up four cup sizes during pregnancy?

IN-STORE APPOINTMENTS

How long does an appointment last?

Appointments tend to last about 15 minutes, but can last for up to 30 minutes in some cases.

Appointments tend to last about 15 minutes, but can last for up to 30 minutes in some cases.

Where should I go when I arrive in store for my bra fit?

Make your way to the lingerie fitting room, where your bra fitter will be ready to welcome you.

Make your way to the lingerie fitting room, where your bra fitter will be ready to welcome you.

INSTANT CALLS AND ONLINE APPOINTMENTS

What is the difference between an instant call and an online appointment?

An instant call will connect you with one of our expert bra fitters there and then. Alternatively, you can make an online appointment for a future time and date.

An instant call will connect you with one of our expert bra fitters there and then. Alternatively, you can make an online appointment for a future time and date.

What can I use the service for?

Most customers use our online service to have an online bra fit. However, you may also want to use the service if you’d like some expert advice on our lingerie. For any other queries or order details, please contact our customer services team, who will be happy to help.

Most customers use our online service to have an online bra fit. However, you may also want to use the service if you’d like some expert advice on our lingerie. For any other queries or order details, please contact our customer services team, who will be happy to help.

Will I be seen on the call?

It’s completely up to you whether to turn your camera on or off. If you’re ringing to have a bra fit, however, we would encourage you to turn your camera on.

It’s completely up to you whether to turn your camera on or off. If you’re ringing to have a bra fit, however, we would encourage you to turn your camera on.

Will I need to remove any clothing?

We do recommend allowing our online bra fitter to see you wearing your bra, as this will help your fitter identify your perfect fit. But it’s totally fine if you’d prefer to keep your top on. In this case, we’d recommend wearing something fitted.

We do recommend allowing our online bra fitter to see you wearing your bra, as this will help your fitter identify your perfect fit. But it’s totally fine if you’d prefer to keep your top on. In this case, we’d recommend wearing something fitted.

What are the best conditions for my appointment? Do I need anything specific?

Our online bra fitters will do their best in all conditions. However, you’ll get the most out of your appointment if you wear your best-fitting bra, have stable internet connection and join your appointment from a quiet, private space. If possible, we’d suggest having a tape measure to hand, too.

Our online bra fitters will do their best in all conditions. However, you’ll get the most out of your appointment if you wear your best-fitting bra, have stable internet connection and join your appointment from a quiet, private space. If possible, we’d suggest having a tape measure to hand, too.

How do I cancel or rearrange my appointment?

You can reschedule or cancel your appointment by following the link in your booking confirmation email.

You can reschedule or cancel your appointment by following the link in your booking confirmation email.

Bra sizes how to calculate

Before using the bra size calculator, we need your measurements! Grab a piece of paper to write down your measurements!

Reference the image that follows to accurately measure yourself using a flexible measuring tape. Record your measurements in inches.

Using these measurements, input them into the bra size calculator below to find out your true bra size.

Tip: Make sure you keep the measuring tape parallel to the floor when standing. It should be straight, not angled! Stand in front of a mirror or get a friend to help!

The Accurate Bra Size Calculator

Using your measurements that you wrote down previously, enter your numbers (in inches) into the Bra Size Calculator fields below:

Recommended Bra Size:

*If you’d like to convert your size to a US or International size, see the bra size conversion charts below!

Please note that all estimated sizes can also depend on your breast shape and you should use it as a starting point to find your best fitting bra! There can be variations between different brands in sizing and even styles. It is recommended that you try on a few bras in the range of this estimated size to find your absolute perfect fit. See our list of where to buy bras in your proper size here.

Bra Size Conversion Charts

This website uses UK sizes, which are highly recommended as US sizing tends to be outdated and sloppy. The main difference is when you start to hit the DD cup size as you will see below. If you’d like to convert your calculated UK size to its US size, use the international bra conversion charts below:

Convert Band Size

Use the chart below to see your converted band size:

Convert Cup Size

Use the chart below to see your converted cup size:

The truth about bra sizing

The good news: most brands outside of the United States already know this and have been manufacturing bras that fit the majority of women for ages. The United Kingdom, for example, knows that breasts are not created in a limited size range and caters to all shapes and sizes. Band sizes ranging from 28 to 52 and cup sizes ranging from AA to J are the norm there, and so they should be!

In many US department stores, the method of sizing they use is outdated and super inacurate. It is common for a lingerie fitter to take your under-bust measurement and add 4 (or even 5!) inches to that number. So if you measure a true 30″ around, your band size would be rounded up to 34″ in order to fit their brand sizing. This results in a less-than-optimal bra fitting because the band is going to be too loose, and the cup size is going to be too small due to the additional band size allowance.

Why are they fitting you into a band size that is NOT your actual measurement?! The answer is simple: to cut manufacturing costs. Less SKUs equals lower production cost. If you measure 30 inches under your bust, your band size should be exactly 30 inches. Quickly run away from any bra fitter who adds additional inches to your measurement!

This website was created to give you your TRUE bra size using your TRUE measurements, which results in the best, most optimal fit you will ever experience. This is how the UK lingerie companies size their bras, and slowly but surely many US manufacturers are moving over to this method. We cannot all be expected to fit into an A, B, C, or D so I truly hope this helps you on your journey to finding the perfect bra!

How a bra should fit

The Band

The band is the one part of the bra that actually supports your breasts. You want the band to be pretty tight and to allow for some stretch as you wear it. When buying a new bra, the clasps should be fastened to the outermost setting to allow for tightening as your bra stretches with wear. The band should not be able to be pulled out more than 2 inches from your back. When you raise your arms, the band should not move.

The Straps

Contrary to what many believe, the straps are not what support your breasts. Your straps should be adjusted so they don’t slide off of your shoulders and don’t cause the back of your bra to ride up. The band should remain parallel to the floor at all times. If straps are digging into your skin, this is a sure sign that they are compensating for too much of your breast weight.

The Cup

Depending on your own breast shape, one style of bra may fit better than another. Full coverage cups, demi cups, and/or plunge cups all fit various shapes of breasts differently. Be sure that your cup has no gaps from any angle. If you notice gaping along the top edge, try a style with a lower cup profile or a smaller cup size. The underwire or side of the cup should encompass all of your breast tissue, including the side area under your armpits.

How The Wrong Size Bra Affects Your Body

It’s no joke that three quarters of women are wearing the wrong bra size. Aside from being uncomfortable, there are some health concerns caused by wearing an incorrect size that shouldn’t be dismissed.

Where To Buy Full Size Bras

Our favourite online stores that offer plenty of size ranges for bras that fit the full spectrum. Because we need more than just A-DD!

7 Signs That Your Bra is the Wrong Size

With a huge majority of women wearing the wrong size bra, have you ever considered that you might be one of them?