The Right Way to Measure Your Bra Size: The Rib Cage Method - BRABAR

The Right Way to Measure Your Bra Size: The Rib Cage Method


Wearing a properly fitting bra can make a world of difference in your comfort and confidence. Yet, many women are still using outdated methods to determine their bra size. In this article, we will guide you through the correct way to measure your bra size using the rib cage method and dispel common misconceptions such as measuring at the armpit level or adding 4 inches to your band size.

Learn How to Measure Your Bra Size

The Importance of Accurate Measurements

Before delving into the rib cage method, it's essential to understand why accurate measurements are crucial. A well-fitting bra provides support, comfort, and enhances your silhouette. An ill-fitting bra can lead to discomfort, back pain, and even posture issues. To avoid these problems, let's explore the correct method for determining your bra size.

The Rib Cage Method: Step by Step

  1. Get Prepared: To begin, you'll need a soft measuring tape, a mirror, and a non-padded, non-wired bra. Stand in front of the mirror wearing your best-fitting non-padded bra.

  2. Measure Your Band Size: Start by measuring your underbust, right under your bust, where your bra band sits. Make sure the measuring tape is snug but not tight against your skin. This measurement is your band size.

  3. Ignore the Armpit Level: A common mistake is measuring at the armpit level to determine your band size. This method is incorrect because it includes the width of your ribcage, leading to an oversized band size.

  4. Understanding the Band Size: Your band size corresponds to the number in your bra size (e.g., 32, 34, 36, etc.). It is a direct measurement and should not be altered or adjusted.

  5. Measure Your Bust Size: Next, measure around the fullest part of your bust while keeping the tape comfortably taut but not too tight. This measurement is your bust size.

  6. Calculating Your Cup Size: To determine your cup size, subtract your band size (underbust measurement) from your bust size. Use the difference to find your cup size on the bra size chart:

    • 1 inch difference = A cup
    • 2 inches difference = B cup
    • 3 inches difference = C cup
    • 4 inches difference = D cup

Debunking the "Add 4 Inches" Myth

Now, let's address the misconception of adding 4 inches to your band size. This outdated practice was once employed to provide additional comfort but is no longer relevant due to advances in bra design and materials.

Adding 4 inches to your band size will result in a band that is far too loose, causing inadequate support and an improper fit. Additionally, this practice impacts your cup size. For example, if your true band size is 32 inches and you add 4 inches, you get 36 inches. With a bust measurement of 36 inches, your cup size will now be incorrectly calculated as AA, when in fact, you may need a larger cup size like a C or D.


Accurate measurements are the key to finding the perfect-fitting bra. By using the rib cage method, you can determine your band and cup size correctly. Remember, there's no need to add 4 inches to your band size or measure at the armpit level. Embrace your true bra size, and you'll experience the comfort and support that a well-fitted bra can offer, enhancing your daily comfort and confidence.

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