The Ultimate Bra Measuring Guide

1. Why the Right Bra Size Matters

Did you know 80% of women wear the wrong bra size? Wearing the wrong size changes how your clothes fit. It can cause discomfort, hurt your posture, and lower your confidence. It can also lead to back pain, shoulder pain, and skin irritation.

A bra that fits well does more than provide support. It shapes your body, improves your posture, and boosts your confidence.

At La Plantureuse, every full-bust woman deserves a bra that fits and feels amazing. That’s why we created this guide to help you measure your size and find the right fit.

Whether you’re measuring for the first time or double-checking your size, this guide will show you how.

Here's what you'll learn:

  • Three simple steps to the perfect bra measurement
  • How to avoid bra measuring mistakes
  • Expert opinions on bra fit
  • Answers to your most asked questions
  • Bra measuring guide: Full-bust woman’s torso with lines indicating band size and cup size, next to a table explaining the difference between band size (ribcage measurement) and cup size (breast volume).

    2.1 How Bra Sizes Work: Band + Cup Explained

  • How They Work Together

    • The band size gives support, while the cup size fits the breast volume. Together, they form the complete bra size (e.g., 48G, 50H).

    • Cup sizes depend on the band size. The same cup letter gets bigger as the band size increases. For example, a 44G has smaller cups than a 48G. You call this sister sizing. It helps you find the right fit.
  • 2.2 The Importance of Sister Sizes

    Sister sizes are bra sizes with the same cup volume but different band sizes. They help you adjust your size for the best fit and comfort without losing support. Here's why sister sizes are important:

  • Bra size chart showing sister sizes for full-bust women, starting at 36DD to 50I, with alternative band and cup size combinations to help with bra measuring and finding the best fit.

Adjusting for Band Fit

  • A snug, supportive band is critical for comfort and stability. If the band of your usual size feels too tight or too loose, moving to a sister size can help:
  • Go up a band size and down a cup size for a looser fit (e.g., 48DDD to 50DD).
  • Go down a band size and up a cup size for a tighter fit (e.g., 48DDD to 46G).

Ensuring Cup Volume Consistency

  • Sister sizes ensure the cup volume remains consistent even if the band size changes. For example, a 48G, 50DDD, and 52DD all have similar cup volumes but different band fits.

Enhancing Comfort and Support

  • Breast shapes and rib cage sizes vary, and not all brands fit the same. Sister sizes help you find a secure fit that doesn’t dig in or slip.

Accommodating Body Changes

  • Changes in weight, pregnancy, or aging can alter your bra fit. Sister sizes let you adjust without changing your whole bra size.

Helping with Limited Availability

  • If your size isn’t available, sister sizes help you find a similar, comfortable fit.

Knowing sister sizes helps you find a fit that’s comfortable and works for your body.

2.3 Common Myths About Bra Sizes

Misunderstandings about full bust sizes can cause poor fits and discomfort. Learning the facts helps you find the right bra and feel confident.

Here are some common myths and the truths behind them:

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Larger Cup Sizes Equal Larger Bodies

Truth: Cup size doesn’t show your full body size.

A person with a 32G bra size has a much smaller band size than someone with a 40G, despite the letter being the same.

Cup volume is relative to band size, meaning a "G" cup on a small band can fit a petite person.

Full Bust Sizes Are Rare or Abnormal

Truth: Full bust sizes are common but hard to find in stores.

Many women wear the wrong size, thinking they must fit into A–D cups.

This causes discomfort and poor support.

Full Bust Sizes Don't Need a Proper Fitted Band

Truth: In full bust sizes, a snug band is even more crucial because it provides the majority of the support.

A loose band shifts the weight to the straps, causing strain and discomfort.

Full Bust Bras Are Always Bulky or Unattractive

Truth: Modern brands offer stylish, lightweight, and supportive full bust bras.

You can choose from sleek designs, lace, and minimal padding.

All Full Bust Bras Are the Same

Truth: Full bust sizes show drastic differences in breast shapes.

A bra that works for one full-busted person may not suit another.

Knowing bra styles and features helps you get the right fit.

Only Padded Bras Provide Adequate Support

Truth: You don’t need padding for support.

Strong materials, firm bands, and underwire provide lift and shape.

Full Bust Bras Are Uncomfortable

Truth: Discomfort is often due to wearing the wrong size or style.

A proper fitted bra in a full bust size can feel comfortable and supportive all day.

3. Step-by-Step Measuring Guide

What You'll Need

  • A soft measuring tape (or a string and a ruler if you don’t have one)

Do you need one? Grab a professional measuring kit here.

  • A mirror to help you see what you’re doing, 

  • Wear a non-padded bra or no bra for the best results. 
Full bust woman using a soft measuring tape around her ribcage to measure her band size, demonstrating the process of bra measuring for an accurate fit.

Measure Your Band Size

Step 1
Full bust woman using a soft measuring tape to measure the fullest part of her bust, demonstrating the proper technique for bra measuring to ensure an accurate fit.

Measure Your Bust Size

Step 2
Image of a hand writing the equation '51 Full Bust minus 42 Band equals 9,' with the result showing as 42I, demonstrating the process of bra measuring to determine the correct bra size.

Determine Your Cup Size

Step 3
Full bust woman using a soft measuring tape around her ribcage to measure her band size, demonstrating the process of bra measuring for an accurate fit.

Measure Your Band Size

Step 1
Full bust woman using a soft measuring tape to measure the fullest part of her bust, demonstrating the proper technique for bra measuring to ensure an accurate fit.

Measure Your Bust Size

Step 2
Image of a hand writing the equation '51 Full Bust minus 42 Band equals 9,' with the result showing as 42I, demonstrating the process of bra measuring to determine the correct bra size.

Determine Your Cup Size

Step 3
Full bust woman using a soft measuring tape around her ribcage to measure her band size, demonstrating the process of bra measuring for an accurate fit.

Measure Your Band Size

Step 1
Full bust woman using a soft measuring tape to measure the fullest part of her bust, demonstrating the proper technique for bra measuring to ensure an accurate fit.

Measure Your Bust Size

Step 2
Image of a hand writing the equation '51 Full Bust minus 42 Band equals 9,' with the result showing as 42I, demonstrating the process of bra measuring to determine the correct bra size.

Determine Your Cup Size

Step 3
Full bust woman using a soft measuring tape around her ribcage to measure her band size, demonstrating the process of bra measuring for an accurate fit.

Measure Your Band Size

Step 1
Full bust woman using a soft measuring tape to measure the fullest part of her bust, demonstrating the proper technique for bra measuring to ensure an accurate fit.

Measure Your Bust Size

Step 2
Image of a hand writing the equation '51 Full Bust minus 42 Band equals 9,' with the result showing as 42I, demonstrating the process of bra measuring to determine the correct bra size.

Determine Your Cup Size

Step 3
  • Step 1: Measure Your Band Size

    • Wrap the measuring tape around your ribcage, right under your bust. Breathe normal while measuring to avoid pulling the tape too tight.

    • Make sure the tape is snug, even, and parallel to the floor. A tilted tape can lead to incorrect measurements.

    • Write down the measurement in inches. If it’s an odd number, round down to the nearest even number. (For Example, Round 31.5 inches to 32 inches.)

    • Always take the measurement twice to ensure accuracy. If the results differ, take a third measurement and use the average.
  • Step 2: Measure Your Bust Size

    • Wrap the measuring tape around the fullest part of your bust, usually across the nipples.

    • Lean forward to allow all the weight to pull towards the floor.

    • ProTip: Taking measurements while you inhale can expand your ribcage and skew the bust measurement. Breathe normal and measure on an exhale.

    Step 3: Determine Your Cup Size

    • Subtract your band size from your bust size.
    • Use this chart to find your cup size (starting at DD)

4. Common Measuring Mistakes and How to Avoid Them

Even with the best intentions, measuring errors happen. A small mistake can lead to an uncomfortable, poor fitting bra. Avoid these common mistakes to ensure your measurements are as accurate as possible:

- Measuring Too Tight or Too Loose -

When it comes to measuring, balance is key. Pulling the tape too tight can squeeze your skin and make the band size too small. But, if the tape is too loose, you’ll end up with a band size that’s too large, compromising the bra’s support. 

How to Avoid:

  • Ensure the tape is snug but not digging into your skin.
  • Double-check the fit in a mirror to make sure the tape lies flat and straight around your torso.

- Using the Wrong Bra for Measurement -

The type of bra you wear during measurement matters. A padded or push-up bra can alter the natural shape of your bust, giving an inaccurate result.

Why a Non-Padded Bra is Best:

  • A non-padded bra lets you measure your natural bust size without extra shaping.
  • Go braless if you're comfortable to avoid outside effects on your measurements.

- Not Measuring at the Right Time -

Your body changes during the day due to water retention and swelling. Measuring at the wrong time can lead to inconsistent results.

When to Measure for Best Accuracy:

  • Measure at the end of the day when your body is most relaxed and any swelling has subsided.
  • Avoid measuring right after intense physical activity, which may temporarily alter your size.

By avoiding these common pitfalls, you’ll be one step closer to finding the perfect fit every time! Ready to learn how to put these measurements to good use? Let’s move on to determining your correct bra size!

  • 5.1 How Different Styles Affect Fit

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    1. Full-Coverage Bras

    Best For: Everyday wear, minimizing spillage, and creating a smooth silhouette.

    Features: Wider straps, higher cups, and reinforced bands for extra support.

    2. Balconette Bras

    Best For: A lifted, rounded shape without excessive coverage.

    Features: Shorter cups and wide-set straps; perfect under low-cut tops.

    3. Plunge Bras

    Best For: Deep necklines and a natural cleavage effect.

    Features: A low center gore that stays supportive without compromising style.

    4. Minimizer Bras

    Best For: Reducing the appearance of your bust by redistributing tissue.

    Features: Broad cups and firm bands for even compression.=

  • Image showcasing 7 bra styles: full coverage, balconette, plunge, minimizer, sports, wireless, and strapless bras, emphasizing the importance of bra measuring for selecting the right fit for different body types and needs.

    5. Sports Bras

    Best For: High-impact activities or extra support throughout the day.

    Features: Compression, encapsulation, or both to minimize bounce.

    6. Wireless Bras

    Best For: Comfort-focused days or lounging.

    Features: Soft cups with supportive bands that prioritize ease.

    7. Strapless Bras

    Best For: Off-the-shoulder or strapless outfits.

    Features: Silicone grips, reinforced bands, and strong underwire for secure fit.

5.2 Tips for Full-Bust and Full Bust Plus Size Comfort

  • Choose wide straps to spread weight and avoid shoulder pain.

  • Choose side panels to keep breast tissue forward for a better shape.

  • Choose breathable fabrics: Especially in hot climates, moisture-wicking materials help keep you cool.

  • Invest in quality: A well-made bra lasts longer and provides better support.

Try different styles to find what works best for your unique shape!

  • Image showcasing different breast shapes: round, teardrop, east-west, asymmetrical, bell shape, slender, relaxed, athletic, and side-set, with a focus on the importance of bra measuring to find the best fit for each unique shape.

    Your breast shape helps decide which bras fit, support, and flatter you best. Here’s a guide to identifying your breast shape and selecting the right bras for your unique needs.

  • 1. Round - Fullness is even on the top and bottom of the breasts.

    Best Bras:

    • T-Shirt Bras: Seamless cups maintain a smooth, rounded shape under clothing.
    • Balconette Bras: Showcase natural fullness with a lifted, open neckline.
    • Plunge Bras: Highlight cleavage without adding bulk.

    2. Teardrop - Fuller at the bottom with slightly less volume on top.

    Best Bras:

    • Full-Coverage Bras: Even out proportions with cups that lift and support.
    • Balconette Bras: Add volume to the upper portion of the breast for a balanced look.
    • Push-Up Bras: Enhance upper-bust fullness for a rounded appearance.

    3. East-West - Breasts point outward with space between them.

    Best Bras:

    • Plunge Bras: Push breasts inward for centered cleavage.
    • T-Shirt Bras: Molded cups smooth and centralize breast tissue.
    • Side-Support Bras: Contain and lift breast tissue toward the center.

    4. Bell Shape - Slimmer at the top and fuller at the bottom.

    Best Bras:

    • Full-Coverage Bras: Provide lift and contain bottom-heavy fullness.
    • Minimizer Bras: Redistribute volume for a sleeker silhouette.
    • Underwire Bras: Offer strong support for the lower part of the breast.

    5. Asymmetrical - One breast is noticeably larger than the other.

    Best Bras:

    • Molded-Cup Bras: Provide structure and conceal size differences.
    • Bras with Removable Padding: Add padding to the smaller breast for balance.
    • Stretch-Cup Bras: Adjust to fit the unique size of each breast.
  • 6. Slender - Breasts are narrow and may have less natural fullness.

    Best Bras:

    • Push-Up Bras: Enhance cleavage and add volume.
    • Plunge Bras: Create a rounded shape and natural lift.
    • Padded Bras: Add fullness for a more proportional look.

    7. Side Set - Breasts sit farther apart with noticeable space in the middle.

    Best Bras:

    • Plunge Bras: Pull breasts inward for a centered effect.
    • Balconette Bras: Enhance shape without excessive coverage.
    • Side-Support Bras: Help direct breast tissue toward the center.
  • 8. Relaxed - Breasts have a looser, softer tissue and may have downward-facing nipples.

    Best Bras:

    • Full-Coverage Bras: Provide lift and contain breast tissue.
    • Underwire Bras: Add structure and prevent sagging.
    • Balconette Bras: Lift and shape without excessive padding.

    9. Athletic - Breasts are wider, more muscular, and may have less natural volume.

    Best Bras:

    • Plunge Bras: Create a natural, lifted shape.
    • Padded Bras: Add softness and volume.
    • T-Shirt Bras: Provide a seamless, rounded appearance.

6. FAQs: Your Bra Measuring Questions Answered

Q: How often should I measure myself?

A: Measure yourself every 6 to 12 months or when your body changes (i.e. after weight shifts, pregnancy, or lifestyle changes).

A good fit ensures comfort and support.

Q: What if my size changes often?

A: It’s normal for your size to change due to hormones, lifestyle, or stress.

Keep a few bras in different sizes and choose ones with adjustable hooks and stretchable bands for comfort.

Q: How do I know if my bra fits correctly?

A: A proper fitting bra should:

  • Have a band that stays level across your back without riding up.
  • Keep your breasts fully contained in the cups without spillage or gaps.
  • Have underwires that sit flat against your chest without digging in or floating away.
  • Feel supportive without causing discomfort.
    If you experience any discomfort or frequent adjusting, it’s a sign that you may need a different size.

Q: What if I’m between sizes?

A: If you’re between sizes, try adjusting the band and strap tension first.

If that doesn’t help, consider sister sizing—this means going up a band size and down a cup size or vice versa.

For example, if 34DD feels a bit tight, try 36D.

Got more questions? Contact us to talk with a professional fitter.

Ready for a Better Fit?

Wearing the right bra size improves comfort, posture, and confidence. It helps your clothes fit better and supports your daily activities. Learning to measure yourself is the first step to finding the perfect fit.

Ready to experience the difference for yourself? Take a few minutes to measure your size using our easy-to-follow guide. 

Don’t forget to download La Plantureuse’s Simple Bra Measuring Guide for a quick reference whenever you need it. 

A well-fitted bra isn’t a luxury—it’s a necessity, and you deserve it!