what does the letter mean in bra size

Understanding Bra Sizes: What Does The Letter Mean?

When it comes to finding the perfect bra, understanding the meaning behind the letter in your bra size is key.

This letter, which ranges from A to K and beyond, is not just a random character but an important indicator of cup size. In this guide, we'll answer the question- what does the letter mean in bra size?

Not only this but also we will cover everything from the basics of bra sizing and how you can choose the right size for you. So, let’s get into the details!

The Basics of Bra Sizing

Finding the right bra size is essential for comfort and support. In the UK, bra sizes are made up of a number and a letter. These two parts tell us about the band size and the cup size.

Band Size (Number)

The number in the bra size stands for the band size. It measures around the ribcage, right under your bust. This is in inches. For example, if you measure 32 inches under your bust, your band size is likely to be 32.

Bust Size (Letter)

The letter in the bra size tells us about the cup size. It represents the volume of your bust. The letter is found by looking at the difference between your bust measurement and your band size. This difference determines your cup size.

To figure out your cup size, start by measuring the widest part of your chest. Then, you subtract the band size from this measurement. Each inch of difference stands for a different cup size. For example, a 1-inch difference might be an A cup, while a 2-inch difference would be a B cup, and so on.

The Difference Matters

The key to understanding UK bra sizes lies in this difference. The band size gives a base, but the cup size shows how much bigger the bust is compared to this base. It's important to get both right for a good fit.

What Does the Letter in Bra Size Mean?

A woman measuring her cup size

The letter in a bra size tells us about the cup size. This part of the bra size is all about the volume of your bust.

Understanding Cup Size

Cup size is found by looking at two measurements. These are your band size and your bust size. The cup size is the letter in the bra size and indicates the breast volume relative to the band size.

The band size is the number part of your bra size. It measures around your body, under your bust. The bust size is how big your bust is at its fullest point.


How Is Cup Size Determined?

To work out your cup size, you first need to know your band size and your bust size. You measure your band size by wrapping a tape measure around the ribcage, under your bust. For your bust size, wrap the tape measure around the fullest part of your bust.

The difference between these two measurements gives you your cup size. Each inch of difference stands for a different letter. For example, a 1-inch difference means an A cup. A 2-inch difference means a B cup, and so on.

In simpler words, To determine your cup size, you need to subtract the band size (underbust measurement) from your bust size (overbust measurement). The difference in inches tells you your cup size., with each inch representing a step up in cup letters (A, B, C, etc.).


An Example

If your band size is 30 inches and your bust size is 33 inches, the 3-inch difference means you have a C cup size.

So, your full bra size would be 30C.

In summary, the letter in your bra size is all about the difference between your band size and your bust size. It shows how much bigger your bust is than your band size.

UK Bra Sizes Guide

This table is a simplified guide; actual bra fit can vary by brand and style. It's always recommended to try on different sizes and styles to find the best fit.


Bra Size

Band, Under Bust (in inches)

Over Bust, Band (in inches)

Under Bust, Cup (in centimetres)

Over Bust (in centimetres)

26AA

22-24 in

22-26 in

56-61 cm

56-66 cm

26A

22-24 in

26-27 in

56-61 cm

66-69 cm

26B

22-24 in

27-28 in

56-61 cm

69-71 cm

26C

22-24 in

28-29 in

56-61 cm

71-74 cm

28AA

24-26 in

24-28 in

61-66 cm

61-71 cm

28A

24-26 in

28-29 in

61-66 cm

71-74 cm

28B

24-26 in

29-30 in

61-66 cm

74-76 cm

28C

24-26 in

30-31 in

61-66 cm

76-79 cm

30AA

26-28 in

26-30 in

66-71 cm

66-76 cm

30A

26-28 in

30-31 in

66-71 cm

76-79 cm

30B

26-28 in

31-32 in

66-71 cm

79-81 cm

30C

26-28 in

32-33 in

66-71 cm

81-84 cm

32AA

28-30 in

28-32 in

71-76 cm

71-81 cm

32A

28-30 in

32-33 in

71-76 cm

81-84 cm

32B

28-30 in

33-34 in

71-76 cm

84-86 cm

32C

28-30 in

34-35 in

71-76 cm

86-89 cm

34AA

30-32 in

30-34 in

76-81 cm

76-86 cm

34A

30-32 in

34-35 in

76-81 cm

86-89 cm

34B

30-32 in

35-36 in

76-81 cm

89-91 cm

34C

30-32 in

36-37 in

76-81 cm

91-94 cm

36AA

32-34 in

32-36 in

81-86 cm

81-91 cm

36A

32-34 in

36-37 in

81-86 cm

91-94 cm

36B

32-34 in

37-38 in

81-86 cm

94-97 cm

36C

32-34 in

38-39 in

81-86 cm

97-99 cm

38AA

34-36 in

34-38 in

86-91 cm

86-97 cm

38A

34-36 in

38-39 in

86-91 cm

97-99 cm

38B

34-36 in

39-40 in

86-91 cm

99-102 cm

38C

34-36 in

40-41 in

86-91 cm

102-104 cm

40AA

36-38 in

36-40 in

91-97 cm

91-102 cm

40A

36-38 in

40-41 in

91-97 cm

102-104 cm

40B

36-38 in

41-42 in

91-97 cm

104-107 cm

40C

36-38 in

42-43 in

91-97 cm

107-109 cm


Please note:


  • The 'Band, Under Bust' column shows the measurement range around the ribcage, right under the bust.
  • The 'Over Bust, Band' column shows the measurement around the fullest part of the bust, which helps determine the cup size.

Common Misconceptions About  Bra Sizes

When it comes to bra sizes, there are many myths. One common myth is about the letter in the bra size. Some people think a larger letter always means larger breasts. This is not true.

The Letter and the Number Work Together

The letter in the bra size tells us about the cup size. But it does not work alone. The number, or the band size, is also very important. The two parts of the bra size work together.

What the Letter Really Means

The letter shows the difference between the band size and the bust size. It's about the volume of the breast in relation to the band size. A larger letter does not always mean a bigger breast size.

Example of Misconception

For example, a 34C and a 36B might sound different. But they can actually be quite similar in breast volume. The difference is in the band size, not just the breast size.

The Truth About Bra Sizes

The truth is, that the right bra size depends on both the letter and the number. You cannot understand one without the other. A bigger letter does not mean bigger breasts for everyone. It all depends on the band size as well.

How to Choose The Right Bra for Your Cup Size

Finding the perfect bra is about more than just size. It's about comfort and style too. Here are some tips to help you choose the right bra for your cup size.

Know Your Size: First, make sure you know your current size. Your body changes over time. It's a good idea to measure yourself regularly.

Consider the Style: Different styles suit different cup sizes. For smaller cups, a demi-cup or push-up bra can add shape. For larger cups, full-coverage bras offer great support.

Look for Good Support: Support is key, especially for larger cups. Look for bras with wider straps and a firm band. This helps distribute weight and adds comfort.

Check the Fabric: Soft, breathable fabrics are best. They should feel comfortable against your skin. Avoid anything that itches or irritates.

Try Different Brands: Not all brands fit the same way. Try on bras from different brands. You might find one brand fits you better than others.

Try on Different Styles: Even if you know your size, different styles can fit differently. Try on various types to see what feels best. You might be surprised by what suits you.

Wrapping Up

And, we are done discussing what the letter does mean in bra size.

The letter in a bra size tells us about the cup size, which shows the volume of the bust in relation to the band size. Please note that the letter doesn't stand alone but works with the band size to give the right fit. Finding the perfect bra involves understanding both these elements. 

Always measure yourself regularly, try different styles and brands, and focus on comfort and support. Remember, a well-fitted bra can make a big difference in how you feel and look.

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