How to Figure Out Your Bust Size: A Step-by-Step Guide

Knowing your accurate bust size is essential for finding the right bra or clothing fit, which can greatly enhance both comfort and appearance. This guide will walk you through each step and provide additional tips and tables to help you easily find your perfect bust size.

Why Bust Size Matters

Wearing the wrong size bra or top can lead to discomfort, poor posture, and even back pain. A well-fitted bra improves your look, helps with confidence, and ensures long-term comfort.

Bust Size Terminology

Before diving into the measurements, let's clarify some key terms:

Term Definition
Bust Size The fullest part of the chest measurement.
Band Size The measurement around the chest, just below the bust.
Cup Size A letter that represents the difference between your bust size and your band size.
Full Bust The fullest measurement across the bust, usually across the nipples.
Underbust The measurement taken directly under the bust, where the band of a bra would sit.

Step-by-Step Guide to Finding Your Bust Size

Let’s walk through how to measure both your bust and band size to calculate the right bra size.

1. Measure Your Band Size

  1. Use a soft measuring tape.

  2. Stand in front of a mirror and wrap the tape around your chest, right under your bust.

  3. Pull the tape snugly but not too tight and make sure it’s level all around.

  4. Note the measurement in inches. Round to the nearest whole number.

    • If the number is even, add 4 inches.
    • If the number is odd, add 5 inches.

This is your band size.

Band Measurement (inches) Add Final Band Size
25-26 +4 30
27-28 +4 32
29-30 +4 34
31-32 +4 36
33-34 +4 38
35-36 +4 40

2. Measure Your Bust Size

  1. Stand up straight and wrap the tape around the fullest part of your chest.
  2. Keep the tape parallel to the floor, without pulling it too tightly.
  3. Note down this measurement to the nearest whole number.

3. Calculate Your Cup Size

Subtract your band size from your bust measurement. Each inch of difference correlates to a specific cup size, as shown in the table below.

Difference (inches) Cup Size
1 A
2 B
3 C
4 D
5 DD (E)
6 DDD (F)
7 G
8 H

Example Calculation:

  • Band size: 34
  • Bust size: 37
  • Difference: 3 inches

The cup size for a 3-inch difference is C. Therefore, the correct bra size is 34C.

Common Challenges and Solutions

1. Fluctuating Measurements

  • Women’s bust sizes can change due to various factors such as hormonal changes, weight fluctuations, and aging.
  • Measure your bust size every six months to ensure an optimal fit.

2. Bra Sizing Systems by Country

  • Different countries use varying sizing standards.
  • Here’s a quick conversion table:
US Size UK Size EU Size FR Size AUS Size
34B 34B 75B 90B 12B
34C 34C 75C 90C 12C
34D 34D 75D 90D 12D

3. Adjusting for Comfort

  • If you fall between sizes, consider adjustable bras that allow band or cup customization.
  • Full coverage bras are often more forgiving if you’re between cup sizes.
Bust Size Chart

 

The following tables provide a general sizing reference based on cup sizes:

 

 

A Cup Sizes

Bra Size Under Bust Fullest Point
32A 26"-28" 31"-33"
34A 28"-30" 33"-35"
36A 30"-32" 35"-37"
38A 32"-34" 37"-39"
40A 35"-37" 39"-41"

B Cup Sizes

Bra Size Under Bust Fullest Point
32B 26"-28" 32"-34"
34B 28"-30" 34"-36"
36B 30"-32" 36"-38"
38B 32"-34" 38"-40"
40B 35"-37" 40"-42"
42B 38"-40" 42"-44"
44B 41"-43" 44"-46"
46B 44"-46" 46"-48"

C Cup Sizes

Bra Size Under Bust Fullest Point
32C 26"-28" 33"-35"
34C 28"-30" 35"-37"
36C 30"-32" 37"-39"
38C 32"-34" 39"-41"
40C 35"-37" 41"-43"
42C 38"-40" 43"-45"
44C 41"-43" 45"-47"
46C 44"-46" 47"-49"

D Cup Sizes

Bra Size Under Bust Fullest Point
32D 26"-29" 34"-36"
34D 28"-31" 36"-38"
36D 30"-33" 38"-40"
38D 32"-35" 40"-42"
40D 35"-38" 42"-44"
42D 38"-41" 44"-46"
44D 41"-44" 46"-48"
46D 44"-47" 48"-50"

DD Cup Sizes

Bra Size Under Bust Fullest Point
32DD 26"-30" 35"-37"
34DD 28"-32" 37"-39"
36DD 30"-34" 39"-41"
38DD 32"-36" 41"-43"
40DD 35"-39" 43"-45"
42DD 38"-42" 45"-47"
44DD 41"-45" 47"-49"
46DD 44"-48" 49"-51"

DDD Cup Sizes

Bra Size Under Bust Fullest Point
32DDD 26"-31" 36"-38"
34DDD 28"-33" 38"-40"
36DDD 30"-35" 40"-42"
38DDD 32"-37" 42"-44"
40DDD 35"-39" 44"-46"
42DDD 38"-43" 46"-48"
44DDD 41"-46" 48"-50"
46DDD 44"-49" 50"-52"

G Cup Sizes

Bra Size Under Bust Fullest Point
32G 26"-32" 38"-40"
34G 28"-34" 40"-42"
36G 30"-36" 42"-44"
38G 32"-38" 44"-46"
40G 35"-41" 46"-48"
42G 38"-44" 48"-50"
44G 41"-47" 50"-52"
46G 44"-50" 52"-54"

Each size provides a specific under-bust and fullest-point range, so you can easily find the most accurate size for comfort and support.

Common Misconceptions

  1. Your band size is your underbust measurement.

    • It’s actually a calculated size, adding 4-5 inches for comfort and fit.

  2. A larger band size will increase cup size.

    • Cups are graded in proportion to the band, so the cup depth changes with the band size.

  3. All bras fit the same.

    • Different styles vary, so you may need to try several to find a perfect fit.

Additional Tips

  • Wear a Non-Padded Bra: For the most accurate measurements, use a non-padded bra.
  • Recheck Annually: Weight changes or lifestyle shifts can impact your bust size, so measure annually.

By following these steps and keeping track of changes in your body, you’ll find the perfect bust size for all your bra and clothing needs.

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