Sizing & International Sizing - Bras N Things

When it comes to bras, women often find themselves in a bit of a bind. What's the right size? How do you convert between different sizing systems? And what about international sizing?

An estimated 80% of women wear the wrong bra size. 70% wear bras that are too small and the other 10% wear ones that are oversize. While most of the reason boils down to wrong bust measurements, some of it is down to the way we convert bra size.

Generally speaking, a bra made by a US company is sized differently from one made in Europe or the UK. Oftentimes, anything above the D-cup has to be converted – and converted correctly. Otherwise, the bra may dig into your breasts and shoulders, causing pain and aches. Chances are, it won’t secure your breasts properly either.

In some cases, a wrong fitting bra may bring about a rash and encourage fungus to grow. That’s because it prevents your skin from getting enough airflow. And it highlights the importance of checking a bra size chart, particularly if you are buying a foreign brand.

 

What is bra size conversion and how does it work?

In simple terms, bra size conversion refers to the process of changing bra size measurements from a unit that’s used in one jurisdiction to one that’s used in another. If, for example, you are based in the US and happen to buy a bra online from a European brand, you will need to convert its size from the European sizing system to the American system.

That will give you a good idea of what bra size to buy because you will ultimately get the measurements in units that you are most familiar with. Think of it like converting distance from meters to feet so that you get a clearer picture of how far (or close) a place is.

Bra conversion works in a simple and straightforward way. If you are familiar with the US sizing system, simply use a bra size chart to convert any other sizing to the US system. Similarly, if you are familiar with a different system – say EU – you would use a bra size chart to convert US and UK measurements in EU measurements.

 

Why do we need to convert bra sizes

The essence of converting bra sizes from one system to another is to know the size that fits you perfectly. It is particularly necessary if you are buying a bra online where you can’t try it on and the seller is a foreign brand. Chances are they will list their sizes based on their country or region’s sizing system. In that case, you would need to convert it to a system that you are familiar with, so that you find a corresponding size that fits you.

It's worth mentioning that bra band and bra cup sizes typically vary from one system to another, and at times between brands. However, it’s a lot easier to convert band size and use it to estimate the right bra size for you.

Cup conversion, on the other hand, can be a bit tricky. That’s because cup labeling systems vary greatly from region to region. This means that the letters used in cups don’t always equate to one another, more so from D-cup and above. For example, while US brands often use DD/E for a 5-inch bra, their European counterparts use E for the same size. UK bra makers use DD.

Generally, cup size labelling falls into two categories. The first is used by the US and UK. Under this system, bra cup sizes increase by an inch. So, you have 1-inch, 2-inch, 3-inch bras and so on.

The second category is used by all other systems. Under this method of labeling, bra cup sizes increase by two centimeters. And since two centimeters is not equal to one inch (1 inch = 2.54 cm), there’s usually a discrepancy between the two labeling systems. This difference becomes more exaggerated as bra cup sizes increase.

Here’s a look at some of the most common bra sizing systems:

US

The US uses inches, and the band size corresponds to chest circumference. Sizes increase by an inch, starting from 0 inches al through 26 inches.

0"	AA
1"	A
2"	B
3"	C
4"	D
5"	DD/E
6"	DDD/F
7"	DDDD/G
8"	H
9"	I
10"	J
11"	K
12"	L
13"	M
14"	N
15"	O
16"	P
17"	Q
18"	R
19"	S
20"	T
21"	U
22"	V
23"	W
24"	X
25"	Y
26"	Z

UK

Similar to the US, the UK system uses inches, and the band size corresponds to chest circumference. It’s also a one-inch system, where cup sizes increase by an inch.

One point to keep in mind is that band sizes start from 26 and increase in twos. Thus, you get bras that start from size 26, 28, 30 and so on. When it comes to cup sizes, every increase per inch increases the cup one level up. However, the lettering (from D-cup) is different from what you will find in the US.

0"	AA
1"	A
2"	B
3"	C
4"	D
5"	DD
6"	E
7"	F
8"	FF
9"	G
10"	GG
11"	H
12"	HH
13"	J
14"	JJ
15"	K
16"	KK
17"	L
18"	LL
19"	M
20"	MM
21"	N
22"	NN
23"	O
24"	OO
25"	P
26"	PP

EU

The European Union sizing uses centimeters rather than inches. While cup sizes increase by 2 centimeters, band sizes increase by 5. Thus, you would have cup sizes from 0, 2, 4, 6 etc. and band sizes in multiples of 5; e.g., 50, 55, 60, 65 etc. To find your true band size, it’s recommended that you measure your band circumference in centimeters, round it off to the nearest 5, then subtract 10.

Belgium, Spain and France (BEF)

These three countries use the same sizing system as the EU. However, the band size here is exactly 15 centimeters greater than the EU size. Thus, a 55-cm band would be 70 centimeters in the BEF sizing system.

 

How to convert a bra size using a chart

To convert bra size from one system to another, you will need your bust size, band size and cup size. All sizing systems use these three measurements – just in different values, particularly from D-cup and above. Here’s a step-by-step process for finding your bra size and converting it:

Step 1: take your bust measurements

Using a measuring tape, measure the fullest part of your bust in inches. This should be where your nipples are, and all round through the back. Make sure the measuring tape runs a bit loosely around your breasts; not too tight and not too loose. A good rule of thumb is to always round off to the nearest whole number.

Step 2: measure your band size

With the measuring tape, measure the area directly under your breasts (in inches). This is your torso, and it is where your bra band would normally be located. You can either do this braless or while wearing a non-padded bra. If you get an even number, add four to it. On the other hand, if you get an odd number, add five to it. So, if for example, you get a band size of 31 inches, you would add 5 to get a total of 36 inches. If the band size is 34 inches, you would add 4 to get 38 inches.

Step 3: find your cup size

Calculate your cup size by subtracting your band size (calculated in step 2) from your bust size (calculated in step 1). For example, if your bust measurements are 38 and your band size is 34, then your cup size would be 4 inches (calculated as 38 – 34 = 4). Now, use the US table above to determine the cup size.

Step 4: convert to other sizing systems

Once you have your cup size in the US format, use the table below to convert it to any other system that you want.

US	UK	EU	Australia	Japan	Italy
AA	AA			A
A	A	A	A	B	A
B	B	B	B	C	B
C	C	C	C	D	C
D	D	D	D	E	D
DD/E	DD	E	DD	F	E
DDD/F	E	F	E	G	F
DDDD/G	F	G	F	H	G
H	FF	H	G	I
I	G	I	H	J
J	GG	J	I
K	H	K	J
L	HH	L	K
M	J	M
N	JJ	N
O	K	O
P	KK	P
Q	L
R	LL
S	M
T	MM
U	N
V	NN
W	O
X	OO
Y	P
Z	PP

NOTE: Your bra size is the band size and cup size put together. So, if you wear band size 34 and cup size C, your ideal bra would be a 34C. in Japan, this is usually written in reverse; i.e., C34.

 

Tips for finding the right bra size when shopping online

1.Make use of the mirror

The first thing you will want to do before making an online order for a bra is to wear the best-fitting bra that you currently have and take a look at it in the mirror. Make sure it actually fits well. The straps should not be slipping or digging into your breasts and shoulders. Similarly, the band should not feel too loose or too tight. If all these conditions are met, then check the size of the bra and order your new one in that exact size.

2. Use a size chart

If you are well familiar with one bra sizing system, you can convert bra size from a foreign system to the one you are familiar with. For example, if you are in the US and buying from a UK brand, you may refer to the bra size chart above to convert from the UK to the US system.

3. Determine your “sister size”

In bra shopping, your “sister size” is a size that has the same bra cup capacity but different band size. If, for example, your best size is 32C, your sister sizes would be 30D and 34B. You would go with a 30D if you want a slightly tighter band or 34B if you want it slightly loose.

What is the purpose of this? It means that if you don’t think your “true” size will fit, you can opt for your sister size instead. Oftentimes when shopping in a store, you can fit your actual size, and if it’s too large, you can try on your sister size with a smaller band size. If it’s too small, then you can try the sister size with a bigger band size.

Of course, if you are shopping online, you won’t have the luxury of trying them on. But you can rely on other customer reviews to see whether the brand’s bras fit perfectly as advertised or if you would need to opt for a sister size instead.

4. Take the online bra fitting quiz

At times relying solely on the manufacturer’s measurements can be misleading. That’s why there are several online bra fitting quizzes – like this one from Triumph. It helps you figure out your most ideal band size and cup size. From there, you can place a bra order based on your ideal measurements as suggested by the quiz. It’s not exactly fool-proof, but the more ideas you get the better.

5.Pay more attention to the band

This is what will provide most of the support. While bra cups hold the breasts securely in place, bands offer most of the support. Therefore, if you have to get any measurement wrong, make sure it’s not the band. That’s why we recommend measuring your band size as accurately as possible. But also keep in mind that some bras are designed to not have a band, yet offer the same amount of support.

6. Do not remove bra tags immediately

After buying a bra online, test it first to make sure that it fits before you remove its tags. If it doesn’t fit, you can always return it and ask for a replacement of a different size. It goes without saying that your ability to return the bra will entirely depend on the seller’s return policy. That’s why it’s always a good idea to inquire if they allow returns before you make a purchase.

 

Sizing charts for popular online stores

As already mentioned, bra fits and sizing may vary from one brand to another. Here’s a sizing chart for the most popular online stores:

Bust minus band

Calvin Klein (US)

Chantelle (EU)

Elomi (UK)

Bust minus band	Calvin Klein (US)	Chantelle (EU)	Elomi (UK)
0"	AA	AA	AA
1"	A	A	A
2"	B	B	B
3"	C	C	C
4"	D	D	D
5"	DD/E	E	DD
6"	DDD/F	F	E
7"	DDDD/G	G	F
8"	H	H	FF
9"	I	I	G
10"	J	J	GG
11"	K	K	H
12"	L	L	HH
13"	M	M	J
14"	N	N	JJ
15"	O	O	K

Find the best adhesive and stick-on bras at Niidor. Our bras are sized to fit as advertised.

Still not sure what size bra is right for you? Check out our reliable bra size helper.