Find Your Real Bra Size
Use the slideshow to the left to find your
Five Measurements and enter them below.

1. Snug Underbust: inches
2. Tight Underbust: inches
3. Standing Bust: inches
4. Leaning Bust: inches
5. Lying Bust: inches
Estimated Bra Size
N/A
Nearest Sister Sizes
N/A N/A
This calculator finds your UK bra size. If you would like to convert to another size, please see the charts below.


Bra fitting. How does it work? No matter what you do, the bra is always an uncomfortable, sometimes painful, necessity. We're told they'll never be comfortable to wear and that we should just deal with the issues the best we can. A band that slides up. Straps that fall down. Underwire that digs in. The ever so unflattering "quadboob." A painful lower back. All of these things and more are what decide whether your bra fits or not. But guess what? You don't have to deal with that anymore. There IS a bra that fits you somewhere out there! And this is your first step to finding it.

Before you begin your hunt for the perfect bra, you should probably get a better estimate of what your bra size actually is. It is estimated that 80% of women are wearing the wrong bra size. You'll see that statistic thrown about all over the web and a variety of companies tout it, claiming they can help you find the right bra size. While the intentions are good, there is a large disparity between not only brands, but in sizing methods. One of the most popular - and also the biggest culprit of ill-fitting bras - is the "+4 sizing method" which forces women into a bra that has too big of a band and too small of a cup.

The community at A Bra That Fits is dedicated to helping women find a perfect fitting bra. Our sizing method uses the Five Measurements (explained in the "How to Measure" section above) to get a more accurate estimation of your bra size. We use UK sizes because these manufacturers tend to be more consistent across brands. We also tend to recommend brands that use UK sizing like Freya, Panache, Curvy Kate, and Elomi as they come in a variety of sizes outside of the typical 32-38, A-DD range that you see in department stores and in mainstream US brands.

Please keep in mind that the calculator's results are merely estimates and should not be considered definite. Certain breast shapes and size ranges may require slightly different methods of calculating bra size. Sometimes, there are size variations between brands and even colors of the same bra. This means you may need to try on a variety of bras surrounding your estimated size before you can find the perfect fit. If you would like a more personalized calculation, please consider posting a Measurement Check on r/ABraThatFits.

Shocked By Your Results?

Don't worry. Most women are.

A = Tiny
B = Small
C = Average
D = Big
DD = Humongous

Does this sound right to you? Think again.

There's widespread misconception that certain cup sizes equate to certain breast size. When people hear "DD" they tend to immediately think "big boobs!" This is not the case, however, because cup size is not static. A bra's cup size is determined relative to its band size. What does this mean? A 36DD is NOT the same as a 30DD - the former holds more volume than the latter. All the DD indicates is that there is a 5 inch difference between your bust and underbust. Each cup letter corresponds to that difference in inches (A = 1, B = 2, C = 3 and so on).

As an example, you might think you're a 34B, when in fact, you could be a 28DD! Both hold the same volume of breast tissue, but the 28DD is meant for a woman with a smaller frame than the 34B. These are called sister sizes, and you can read more about them here.

DD is not the end of the bra size spectrum. In fact, there are bras out there that are regularly manufactured in sizes up to a KK (making the DD a pretty average cup size). These shocking cup sizes do exist, so don't despair! There is a bra out there for you.

You'll probably have many more questions after using our calculator, so head on over to our Frequently Asked Questions to find the answers.

Ill-fitting bras are not a problem unique to bigger busted ladies. Even if you think your breasts are small, you don't have to settle with the bras you find in department stores. There are options out there for all shapes and sizes. Once you find that perfect bra, you'll wonder how you could ever suffer through those old ones again and your breasts, back, posture, and the rest of your body will thank you.

Converting Your Bra Size

We highly recommend using the UK bra sizing method and buying from UK brands, as these bras tend to be more consistent and come in a variety of sizes to suit your needs.

That being said, if you find a brand that uses another sizing method and need to convert your given bra size, this chart should do the trick.

Please keep in mind, once again, that US/EU/BEF/AU models are not as standardized as the UK model is. Not every brand follows the same model. To complicate matters further, EU and BEF models use centimeters to find the band size, so cup sizes don't always translate directly to their UK/US/AU counterparts, especially after an H cup (UK FF).

If you would like to read more on how to convert your bra size to EU, AU, FR, or another model, please visit the Busty Resources Wiki page here

Band Size Conversion

Underbust* (in) UK US EU AU BEF
25-26
27-28
29-30
31-32
33-34
35-36
37-38
39-40
41-42
43-44
45-46
47-48
49-50
51-52
53-54
55-56
57-58
59-60
26
28
30
32
34
36
38
40
42
44
46
48
50
52
54
56
58
60
26
28
30
32
34
36
38
40
42
44
46
48
50
52
54
56
58
60
55
60
65
70
75
80
85
90
95
100
105
110
115
120
125
130
135
140
4
6
8
10
12
14
16
18
20
22
24
26
28
30
32
34
36
38
70
75
80
85
90
95
100
105
110
115
120
125
130
135
140
145
150
155
*Since our calculator uses inches to find your bra size, these underbust measurements roughly correlate to each band size. Centimeters are more exact, but we didn't want to confuse anybody by adding them in.


Cup Size Conversion

In. Difference UK US EU AU BEF
0.5
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
AA
A
B
C
D
DD
E
F
FF
G
GG
H
HH
J
JJ
K
KK
L
LL
AA
A
B
C
D
DD/E
DDD/F
G
H
I
J
K
L
M
N
--
--
--
--
AA
A
B
C
D
E
F
G
H
*
*
*
*
*
*
*
*
*
*
AA
A
B
C
D
DD
E
F
FF
G
GG
H
HH
J
JJ
K
KK
L
LL
AA
A
B
C
D
E
F
G
H
*
*
*
*
*
*
*
*
*
*
*After cup size H, EU and BEF sizes don't translate from UK/US sizes as well, due to the use centimeters instead of inches. The same is true for AU sizes after an F cup, although this is mainly due to a lack of standardization in the sizing models.