Finding the perfect bra can be a daunting task for many women. With so many sizes, styles, and brands to choose from, it's easy to feel overwhelmed. However, understanding how bra sizes work and what the different numbers mean is essential in order to find a comfortable and well-fitting bra.

Wearing the incorrect bra size can lead to various problems, such as discomfort, and back pain, whereas a well-fitting bra can boost your confidence and have you ready to take on the day.

Our comprehensive guide to what bra sizes mean will help you understand the basics and decode the meaning behind the numbers and letters, bust some common myths and misconceptions, as well as provide tips for finding your perfect bra size.

How Do You Calculate Bra Size?

  1. To calculate your bra size, first, you need to measure around the fullest part of your bust with a tape measure held parallel to the ground. This measurement is known as your bust circumference.
  2. Next, measure around your ribcage just below your breasts using the same parallel tape measure technique. This measurement is known as your underbust circumference.
  3. To calculate your cup size, subtract your underbust measurement from your bust measurement and consult a bra size chart. The difference in inches between these two measurements corresponds to an alphabetical cup size (e.g., 0-1 inch difference = A cup, 2-inch difference = B cup).

How To Measure Band Size

To measure your band size, use a soft measuring tape and wrap it around your ribcage directly under your breasts. Ensure that the tape is snug but not too tight, and parallel to the ground.

Round off the measurement to the nearest whole number. If you get an odd number, add one inch to get an even number – this will be your band size.

How To Measure Cup Size

For your cup size, measure around the fullest part of your breasts while wearing a non-padded bra. Make sure the tape is parallel to the ground and not too tight. Subtract your band size from this measurement. The difference between these two measurements determines your cup size.

Bra Sizes Explained

bra sizes explained - women in white bra

What Does The Number On A Bra Size Mean?

The number on a bra size refers to the band size, which is the measurement of your ribcage just below your breasts. This measurement determines how snugly the bra fits around your body and provides support for your breasts.

The band should fit comfortably without digging into your skin or riding up in the back. If it does ride up, you may need to adjust the band size and go down a size.

It's important to note that as band sizes increase, so do cup sizes - this means that a 36C has a larger cup than a 34C, but both have the same cup volume.

Understanding your correct band size is crucial for finding bras that fit well and provide adequate support for everyday wear or special occasions alike.

What Do The Letters Mean On A Bra Size?

The letters in a bra size represent the cup sizes. These alphabetical cup sizes vary depending on the difference between your band size and bust measurement:

  • A: 1-inch difference
  • B: 2-inch difference
  • C: 3-inch difference
  • D: 4-inch difference

...and so on. The combination of the band size and cup size (e.g., 34B) indicates your complete bra size.

Different countries may have different sizing systems for bras. For instance, the UK, US, EU, and other regions may use slightly varying cup sizes or measuring units. Use our bra size conversion chart to help you if you're buying lingerie from different international brands.

International Bra Size Conversion Chart


BUST MINUS BAND

UK CUP SIZES

US CUP SIZES

EUROPEAN

CUP SIZES

less than 1"

AA

AA

AA

1"

A

A

A

2"

B

B

B

3"

C

C

C

4"

D

D

D

5"

DD

DD/E

E

6"

E

DDD/F

F

7"

F

DDDD/G

G

8"

FF

H

H

9"

G

I

I

10"

GG

J

J

11"

H

K

K

12"

HH

L

L

13"

J

M

M

14"

JJ

N

N

15"

K

O

O



Why Are Bra Sizes So Confusing?

There are a few different reasons that contribute to the confusion that is bra sizing. One of the primary factors is that there is no universal sizing system across different brands and manufacturers. Each company may use different measurements or fit models, leading to inconsistencies in sizing.

A second reason is size conversion. Despite some brands trying to adhere to the same system of fit and proportion, different countries have their own unique sizing systems.

As a result, depending on where the brand is based, the size you typically wear may vary significantly. You might be a 32B in one brand in the UK, but then in Spain, you could be a completely different size.

The challenge with navigating this issue is not only finding your correct size within each brand's range but also being able to accurately convert between them when purchasing bras from international retailers or online stores.

This highlights how complex and nuanced bra sizes can often be – requiring both patience and persistence when shopping for lingerie that fits comfortably and flatters your figure perfectly.

Finally, another factor contributing to confusion around bra sizes is societal pressure surrounding body image.

Some individuals might feel ashamed or embarrassed if they do not fit into traditional beauty standards set by society, which often include having a certain bra size leading them to shy away from finding well-fitting bras and buying the same size for years on end even when their body has changed due to weight gain, childbirth or ageing.

Ultimately, it can be difficult to find the perfect bra fit which is why we always recommend heading to a lingerie expert like our founder, Susana Lorena. Here at Maison SL, we can find your perfect fit in a style that suits you. 

By educating yourself on proper measurement techniques and finding brands that work well with your unique shapes, you can alleviate some of the confusion surrounding bras.

What Are Sister Sizes In Bras?

Sister sizes refer to bra sizes that have the same cup volume but different band sizes. For example, a 34C and a 36B are sister sizes – both have the same cup volume but with different band sizes. This is helpful to know when trying on bras, as you may find that a sister size provides a more comfortable fit.

Common Myths and Misconceptions about Bra Sizes

Myth: A Bigger Cup Size Always Means Bigger Breasts

It's not uncommon for people to assume that a larger cup size automatically equates to having larger breasts. However, this is far from the truth as there are several factors involved in determining bra sizes. One of the most important aspects of finding the perfect fit is understanding that cup size is relative to band size.

To put it simply, a 34D and a 36D may both have the same "D" cup size but their overall volume will differ significantly due to differences in their respective band sizes. In essence, if you were to compare these two bras side by side, you would notice that the cups on the 36D appear much larger than those on the 34D.

Myth: Once You Know Your Bra Size, It Will Remain the Same Forever

Our bodies change over time due to various factors, such as weight fluctuations, hormonal changes, and ageing. This means that your bra size may also change throughout your life. Regularly measuring yourself and getting professionally fitted can help ensure you're wearing the correct bra size.

Myth: All Bras In Your Size Should Fit You Perfectly

As mentioned earlier, different breast shapes may require different bra styles. Even if a bra is technically your size, it may not provide the best support or comfort due to your specific breast shape.

Tips for Finding the Perfect Bra Size

Importance of Trying on Different Styles and Brands

There's no one-size-fits-all when it comes to bras. Each person's breasts are unique, so trying on various styles and brands can help you find the perfect fit.

How to Tell If a Bra Fits Well

A well-fitting bra should feel comfortable, provide adequate support, and have no gaping or spillage. The band should be snug but not too tight and should sit parallel to the ground. The straps should not dig into your shoulders or slip off easily.

Getting a Professional Bra Fitting

A professional bra fitting can be immensely helpful in finding your perfect bra size. Good quality lingerie shops, like Maison SL in West London, should offer this service. A professional fitter can guide you through the process of measuring your size, recommend suitable styles for your breast shape, and help you find the right fit.

Final Words

Understanding bra sizes and what they mean can make all the difference in finding a comfortable and supportive bra. By familiarising yourself with the basics of bra sizing, debunking common myths, and trying on various styles and brands, you'll be well on your way to discovering the perfect bra for you.

Remember that investing time and effort in finding the right bra size is an investment in your comfort, well-being, and confidence.

July 18, 2023
Tags: Blog