How To Find Your Bust Size With Your Bra Size

Did you know that you can find out your bust size just by knowing your bra size? When trying to find new clothes you might notice that there is a bust measurement listed. It helps to know your bust size when it comes to these important buying decisions. If you don't have a measuring tape handy, you're in luck because we have bra and bust size charts and calculators right here for you!

If you know how to find your proper bra size, you are already a step ahead of some women. Unfortunately, there is still some confusion around how to properly measure for your bra.

Maybe you already know what bra size works best for you. If so, that's perfect! We can find out what your bust size is just by using your bra. Bra sizes consist of two important elements; an even number alongside a letter. The even number denotes the underbust measurement used for the band of the bra, and the letter is the cup size. All cup sizes correlate to the difference between your band measurement and your bust measurement. If you're a 32C, your band is 32" and your bust is 35". We know this because every inch difference between your bust and band measurement means you go up a cup.

So when looking at cup sizes AA=0, A=1, B=2, C=3, D=4, and so on. If your band measurement is 34, and your bust is 36, this means your bra size should be 34B since the difference is 2. But instead of doing your own math, you can just use this bust size calculator. To use the calculator, simply enter your bra size. The first field is the number (band) and the second field is the letter (cup size).

Bust Size Calculator

Please enter measurements for both the band and cup size.
Band measurements can only be even numbers.
Your Bust Size:
Enter Band Measurement (Inches) and Cup Size

Find Your True Bra Size

Now if you've never properly taken measurements for your bra size, you may still want to do this. If you feel that there is room for improvement in your overall bra fit, it's definitely worth the effort to take your measurements. There are still many women dealing with the struggles of wearing a bra that isn't sized correctly. So let's take a deeper dive into taking these measurements.

  1. To find your band size this should be measured standing up without a bra. Firmly wrap the measuring tape around your body and underneath your bust. Measuring in inches, if you happen to land on an odd number you round up to the nearest even number. Do not add any other numbers to this measurement. The antiquated method of adding numbers to the band measurement will result in an improper fit.
  2. To find your bust/cup size take your measurements wearing your current favorite non-padded bra, it also cannot be a sports bra. Then you wrap the tape around your body, keeping it straight and measure at the fullest part of your bust.
  3. It's important to keep in mind that everyone is different, and there are many different brands and styles of bras with their pros and cons. This can lead to variation within what makes the perfect fit for you. These resulting measurements are the best way to get your baseline for the best bra fit.
where to take measurements for bra sizing

Now that you have taken your underbust and overbust measurements, you can use the bra size calculator to find out what your bra size is. Remember, this is your recommended benchmark size and you may find that there is some slight variation depending on what style of bra you try on.

Bra Size Calculator

Please enter valid values for both the underband and overbust.
Bust Measurement Cannot Be Less Than Band Measurement
Your Bra Size:
Enter Your Measurements in Inches

Bra Size Charts

The following is a set of bra size charts as an alternative to our calculator. These are some examples from many different cup sizes. Sometimes you may see a range of sizes in a size chart, but we wanted to provide the most accurate bra sizing guides we could. It isn't helpful to give you estimated sizing for each bra size. As previously stated, there may always be a given variation from one bra to the next. Start with your most accurate size to use as your baseline.

AA Cup
US Inches
Bra Size Band
(Under Bust)
(Over Bust)
30AA 30 in 30 in
32AA 32 in 32 in
34AA 34 in 34 in
36AA 36 in 36 in
38AA 38 in 38 in
40AA 40 in 40 in
42AA 42 in 42 in
44AA 44 in 44 in
46AA 46 in 46 in
48AA 48 in 48 in
50AA 50 in 50 in
52AA 52 in 52 in
54AA 54 in 54 in
A Cup
US Inches
Bra Size Band
(Under Bust)
(Over Bust)
30A 30 in 31 in
32A 32 in 33 in
34A 34 in 35 in
36A 36 in 37 in
38A 38 in 39 in
40A 40 in 41 in
42A 42 in 43 in
44A 44 in 45 in
46A 46 in 47 in
48A 48 in 49 in
50A 50 in 51 in
52A 52 in 53 in
54A 54 in 55 in
B Cup
US Inches
Bra Size Band
(Under Bust)
(Over Bust)
30B 30 in 32 in
32B 32 in 34 in
34B 34 in 36 in
36B 36 in 38 in
38B 38 in 40 in
40B 40 in 42 in
42B 42 in 44 in
44B 44 in 46 in
46B 46 in 48 in
48B 48 in 50 in
50B 50 in 52 in
52B 52 in 54 in
54B 54 in 56 in
C Cup
US Inches
Bra Size Band
(Under Bust)
(Over Bust)
30C 30 in 33 in
32C 32 in 35 in
34C 34 in 37 in
36C 36 in 39 in
38C 38 in 41 in
40C 40 in 43 in
42C 42 in 45 in
44C 44 in 47 in
46C 46 in 49 in
48C 48 in 51 in
50C 50 in 53 in
52C 52 in 55 in
54C 54 in 57 in
D Cup
US Inches
Bra Size Band
(Under Bust)
(Over Bust)
30D 30 in 34 in
32D 32 in 36 in
34D 34 in 38 in
36D 36 in 40 in
38D 38 in 42 in
40D 40 in 44 in
42D 42 in 46 in
44D 44 in 48 in
46D 46 in 50 in
48D 48 in 52 in
50D 50 in 54 in
52D 52 in 56 in
54D 54 in 58 in
DD/E Cup
US Inches
Bra Size Band
(Under Bust)
(Over Bust)
30DD 30 in 35 in
32DD 32 in 37 in
34DD 34 in 39 in
36DD 36 in 41 in
38DD 38 in 43 in
40DD 40 in 45 in
42DD 42 in 47 in
44DD 44 in 49 in
46DD 46 in 51 in
48DD 48 in 53 in
50DD 50 in 55 in
52DD 52 in 57 in
54DD 54 in 59 in
US Inches
Bra Size Band
(Under Bust)
(Over Bust)
30DDD 30 in 36 in
32DDD 32 in 38 in
34DDD 34 in 40 in
36DDD 36 in 42 in
38DDD 38 in 44 in
40DDD 40 in 46 in
42DDD 42 in 48 in
44DDD 44 in 50 in
46DDD 46 in 52 in
48DDD 48 in 54 in
50DDD 50 in 56 in
52DDD 52 in 58 in
54DDD 54 in 60 in
G Cup
US Inches
Bra Size Band
(Under Bust)
(Over Bust)
30G 30 in 37 in
32G 32 in 39 in
34G 34 in 41 in
36G 36 in 43 in
38G 38 in 45 in
40G 40 in 47 in
42G 42 in 49 in
44G 44 in 51 in
46G 46 in 53 in
48G 48 in 55 in
50G 50 in 57 in
52G 52 in 59 in
54G 54 in 61 in
H Cup
US Inches
Bra Size Band
(Under Bust)
(Over Bust)
30H 30 in 38 in
32H 32 in 40 in
34H 34 in 42 in
36H 36 in 44 in
38H 38 in 46 in
40H 40 in 48 in
42H 42 in 50 in
44H 44 in 52 in
46H 46 in 54 in
48H 48 in 56 in
50H 50 in 58 in
52H 52 in 60 in
54H 54 in 62 in
I Cup
US Inches
Bra Size Band
(Under Bust)
(Over Bust)
30I 30 in 39 in
32I 32 in 41 in
34I 34 in 43 in
36I 36 in 45 in
38I 38 in 47 in
40I 40 in 49 in
42H 42 in 51 in
44I 44 in 53 in
46I 46 in 55 in
48I 48 in 57 in
50I 50 in 59 in
52I 52 in 61 in
54I 54 in 63 in