Bras Sizes & Cup Sizes Charts, How to Measure + Conversion

Bra Size Chart: You deserve great support and comfort. Get detailed information on how to measure your bra size. Bra Size Charts and Cup Size Calculator for US, UK, AU, NZ, Brasil, South America, European Sizes like Italian and French Sizes in Inch and Centimeters. Plus find your “sister sizes” for a perfect fit. 

Bra Size Calculator Inch and CM

This bra size calculator helps determine correct size in US, UK, and European systems by using bust and underbust measurements in inches or centimeters. Simply input measurements and click “Calculate” for results.

Bra Size Chart

Basic Bra Size Chart

Use a measuring tape to get accurate bust and underbust measurements in inches or centimeters. Refer to our bra size charts, but keep in mind that measurements may vary.

Band Size Chart

US Band SizeInches (in.)Centimeters (cm.)
282858 – 62
303063 – 67
323268 – 72
343473 – 77
363678 – 82
383883 – 87
404088 – 92
424293 – 97
444498 – 102
4646103 – 107
4848108 – 112
5050113 – 117
5252118 – 122
5454123 – 127
5656128 – 132
5858133 – 142

Cup Size Chart

US Cup SizeDifference Between Bust Size and Band Size
Inches (in.)Centimeters (cm.)

At a Glance

  • There are two main measurements being considered when fitting bras: (1) the band size and (2) the cup size.
  • The band size of a bra is determined by measuring the underbust circumference, which is under the breasts in the ribcage area. In the US, band sizes are usually measured in inches and are rounded to the nearest even number.
  • The cup size of a bra is determined by the difference between your underbust and bust measurement, and then converted to an alphabetical letter on the U.S. cup size chart.
  • The “sister sizes” of a bra are other sizes that have the same cup volume, even if the band and cup size are different. You can find your sister size by going up or down one size.
  • Only 48% of women wear the right bra size. Wearing an ill-fitting bra can cause headaches and neck pains, which may eventually lead to posture problems. You might even suffer from breathing problems, and even worse, it might negatively affect the lymphatic system.

Bra Sizes – How Do They Work?

Bra Sizes – How Do They Work?

Bra sizing can be difficult due to varying standards across brands and styles. Two main measurements are considered when fitting bras: band size (underbust circumference) and cup size (difference between bust and underbust). In the US, band sizes are measured in inches and cup size is determined by converting the difference between bust and underbust to an alphabetical letter. A recommended bra size is determined by combining the band size and cup size, for example, 32B.

Bra Sister Size Chart – How It Works

“Sister sizes” are alternative bra sizes that have the same cup volume as your original size, even if the band size and cup letter are different. To find your sister sizes, you can go one size up or down in band size and adjust the cup letter accordingly. For example, if your bra size is 34C, your sister sizes are 32D and 36B. Use a chart to help identify the appropriate sister sizes. The sizes next to your real bra size (one size up or down) are your sister sizes.


International Conversion Chart for Bra Sizes

There will be instances in which you might find yourself purchasing a bra from a foreign brand following a slightly different sizing system. Should you need to convert European sizes to U.S. sizes, or find your corresponding size in Japanese or Australian sizing standards, then you need to refer to a reliable international conversion chart for bra sizes as provided below.

Band Size Conversion Chart

Inches (in.)Centimeters (cm.)US/MX/UKEU/JPITAU/NZ
2858 – 62286006
3063 – 67306518
3268 – 723270210
3473 – 773475312
3678 – 823680414
3883 – 873885516
4088 – 924090618
4293 – 974295720
4498 – 10244100822
46103 – 10746105924
48108 – 112481101026

Cup Size Conversion Chart

Difference Bust Size and Band Size (Inch)Centimeters (cm.)US/MXUKEU000AU/NZ

How to Measure Your Bra Size

How to Measure Your Bra Size

Accurately determine bra size by measuring band and cup size with a measuring tape. Get assistance or take measurements while standing upright and without wearing a bra or loose clothing.

Step 1: Measure Your Band Size

To measure your band size, also known as your underbust width, wrap a measuring tape around your chest directly under your breasts. Make sure you are breathing normally, and your chest is relaxed. Do this twice, first with the tape resting loosely and then with it slightly tighter, allowing it to pinch the skin slightly. Write down both measurements in inches and centimeters, and round the underbust girth to the nearest even number. This will help you determine the correct band size for your bra.

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Step 2: Measure Your Bust Size

To measure your cup size, wrap a measuring tape around your upper torso on top of the highest point of your breasts (nipples). Make sure the tape is level and parallel to the ground. Write down the measurement in inches and centimeters. Use this measurement to look up your bra size in our size chart or bra size calculator.

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Step 3: Calculate Your Cup Size

To determine cup size, get the difference between bust size and band size (measured in the same units, either inches or centimeters). Refer to a size chart to find the alphabetical equivalent of your cup size. A bra size calculator can also be used to determine the best fitting bra sizes by inputting underbust width and bust size measurements.

How to measure bra size without measuring tape

  1. It is easy to measure your bra size without a tape measure.
  2. Use some string or a cord instead of the measuring tape.
  3. Wrap the string around your bust first under the bust line, then on the bust line.
  4. Note of the exact length with a pen. Determine the correct dimensions by using a straightedge or folding ruler.

Wearing the Right Bra Size is Important

Choosing the right bra is crucial for not just fashion, but also health. Wearing an ill-fitting bra can cause headaches, neck pain, posture problems, breathing difficulties, and even harm your lymphatic system. It’s important to determine your correct bra size to avoid these issues and ensure a comfortable fit.

Signs You Are Wearing the Wrong Bra Size

  • Cups wrinkling: Try smaller cup size with same band size
  • Underwires poking: Try larger cup size or different bra style with full coverage
  • Band riding up: Try smaller band size or different bra style like backless, front closure, posture bras
  • Band digging into skin: Try larger band size
  • Cup spillage: Try larger cup size or different bra style
  • Under boobs: Try smaller band size or larger cup size
  • Straps slipping off: Try different cup size, band size or bra style
  • Straps digging into shoulders: Try larger cup size, bra style with tighter band and underwires.

If you encounter any of these red flags, it’s time to reassess your bra size. You can try adjusting the bra or seek professional advice to find a better fitting bra.

Types of Bra Styles

Bras come in different styles such as bralette, full cup, demi, balconette, bandeau, T-shirt, convertible, push-up, plunge, strapless, minimizer, sports, and nursing. Each style serves a specific purpose and provides different features such as support, shaping, comfort, and ease of use. Some bras are designed for specific activities like sports or nursing, while others are designed to enhance the appearance of the bust or to provide flexibility in wearing. It’s important to choose the right style of bra that suits your needs and preferences.

Bra type overview
5 different bra styles Study – Only 48% of Women Wear the Right Bra Size

A lot of women, as it turns out, do not wear the right bra size. This is because many of them do not take the time to consult with a professional regarding their bra size or even take their own measurements. Instead, these women rely on the size of their old and used bras when shopping for new ones. This is supported by our study participated by 1,285 women who were asked in an online panel about bra sizes. Result of the survey showed the following:

  • Only 48% of women wear the right bra size.
  • 16 % of all women wear a bra that is too small; 4 % wear a bra that is significantly too small.
  • 26% wear a bra that is too big; 6% wear a bra that is significantly too large.
  • 82% of the women said that when buying a new bra, they mainly use their previous bra size as their standard. Only 18 % allow a professional to take their measurements or take the time to measure themselves before making a purchase.
  • 74 % of the surveyed women find the existing sizing system for bras confusing, particularly the different methods for determining the band size and cup size.
  • Young women often incorrectly assume their bra size. However, as it turns out, women over 40 years of age are actually more likely to pick the wrong size for themselves.
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