Bust Size vs. Bra Size: How to Find Your Perfect Fit

Are you confused about bust size, bra size, and cup size? You’re not alone! 80% of women wear the wrong bra size, often because they don’t know how to measure correctly. At BRABAR, we’re here to change that.

In this guide, we’ll help you understand bust size vs. bra size , show you how to calculate your cup size, and make sure you get the perfect fit—every time.

Bust Size vs. Bra Size: How to Find Your Perfect Fit

What Is Bust Size?

Your bust size is the measurement around the fullest part of your chest. This number is essential for determining your bra size and cup size.

How to Measure Your Bust Size

  1. Use a soft measuring tape and wrap it around the fullest part of your bust.
  2. Keep the tape level and snug, but not too tight.
  3. Note the measurement in inches—this is your bust size.

💡 Pro Tip: Stand in front of a mirror to ensure the tape is straight across your back.

What Is Bra Size?

Your bra size is a combination of:
Band Size – The measurement around your ribcage, just under your bust.
Cup Size – The difference between your bust size and band size.

How to Calculate Bra Size

  1. Measure Your Band Size – Wrap the tape snugly around your ribcage, just under your bust.
  2. Measure Your Bust Size – Follow the steps above.
  3. Find Your Cup Size – Subtract your band size from your bust size:
Difference (Bust - Band) Cup Size
1 inch A
2 inches B
3 inches C
4 inches D
5 inches DD/E

👉 Example:

  • Bust Size: 34 inches
  • Band Size: 32 inches
  • Cup Size: 34 - 32 = 2 inchesB cup
  • Final Bra Size: 32B

Bust Size vs. Cup Size: What's the Difference?

Many people think cup size is universal—but it actually depends on band size. For example, a 34B and a 36B have different cup volumes because the band is wider on the 36B.

This is why sister sizing is important! If your bra is too tight, go up a band size and down a cup size (e.g., 32C → 34B). If it’s too loose, do the opposite (e.g., 36B → 34C).

💡 Want an easier way to find your size? Use our Bra Size Calculator for instant results!

Why the Right Bra Size Matters

Wearing the wrong bra size can cause:
Straps that dig in or fall off
A band that rides up or feels too tight
Gaps or spillage in the cups
Back and shoulder pain

At BRABAR, we believe that comfort is confidence—which is why we created bras that actually fit real bodies.

No Wires, Only Comfort at BRABAR

Say goodbye to underwires and hello to all-day comfort with BRABAR!

A Bralette & Sports Bra Had a Baby – The perfect hybrid fit.
Dreamy, Comfy, Supportive – Soft, seamless, and wire-free.
Designed for Every Body – Fits AA-DDD/F cups and 28-38 bands.

🎯 Find your fit today! Check out our Fit Guide and shop wire-free bras designed for you.

💖 No wires. No guessing. Just the perfect fit.

🔗 Shop BRABAR Now

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