How To Properly Measure For A Bra Size

Let’s be honest: buying a bra can feel like trying to solve a Rubik’s Cube while blindfolded. You walk into a store, grab something cute, and pray it doesn’t turn your ribcage into a hostage situation. Spoiler alert: most of us are wearing the wrong size. But don’t worry—I’ve got you covered, literally.

Why This Matters (A Lot)

A bad bra is like a bad boyfriend: it digs into you, leaves marks, and makes you miserable all day. Getting the right size is life-changing. It will boost your posture, your confidence, and your ability to breathe without rebellion.

Plus, 80% of women are wearing the wrong size. You are not alone in this awkward, underwire-y wilderness. Let’s fix that.

What You’ll Need

First, grab a soft measuring tape—the kind you’d find in a sewing kit. No tape? No problem. Use a string and then measure that string against a ruler. Just don’t use a metal ruler; your skin will not appreciate the attitude.

You’ll also need a mirror (for those contortionist moves) and a notepad. And yes, you can do this solo, but having a friend helps. Just make sure they’re not the type who laughs at your “pinch an inch” dance.

Step 1: The Band Size (The Foundation)

Stand up straight, but don’t puff out your chest like you’re about to arm-wrestle a superhero. Relax. Wrap the measuring tape directly under your bust, where the band of your bra usually sits.

Tighten it until it’s snug—like a firm hug, not a python squeeze. Round this number to the nearest whole inch. If you’re a 32, great. If you’re a 34.5, round up to 35. But wait: if it’s an odd number, add 4 inches. This is the weird math of bra sizing. Don’t question it; just nod and add.

For example: if your underbust is 31 inches, add 4 to get 35. But if your underbust is 32, that’s already even, so your band size is 32. Pro tip: Your band size should be the same number you need to hook on the loosest clasp—because bras stretch over time like our patience at 5 PM.

Step 2: The Bust Size (The Tricky Part)

Now, measure around the fullest part of your chest. Don’t hold the tape too tight—let it rest naturally, like a lazy cat on a sunny windowsill. Breathe normally (no holding your breath for a smaller number).

Round to the nearest whole inch. Got it? Good. Write that number down. This is your bust measurement. Feels empowering, right? You’re basically a mathematician now.

Step 3: Cup Size – The Magic Math

Here’s where the wizardry happens. Subtract your band size from your bust measurement. The difference determines your cup letter. One inch = A, two inches = B, three = C, four = D, five = DD, six = DDD. Yes, it’s like alphabet soup, but you’re the chef.

Let’s say your band size is 32 and your bust is 35. That’s a 3-inch difference, so you’re a C cup. Congratulations, you’re a 32C! If the difference is 5 inches, you’re a 32DD. Don’t freak out about as, bs, or dds—letters are just letters, and they don’t define your worth.

How to Measure Your Bra Size Correctly | Step-by-Step Guide

Step 4: The “Sister Sizing” Escape Hatch

What if a 32C feels too tight in the band but too big in the cups? That’s where sister sizes come in. Sister sizes are like bra cousins—they share the same cup volume but different band and cup combos.

Example: If you’re a 32C, your sister size is 34B (go up a band, down a cup) or 30D (down a band, up a cup). Use this magic when you fall in love with a bra that doesn’t exist in your exact size. Just remember: the band should fit snugly, not slide up your back like a runaway Slinky.

Step 5: The Fit Test (Don’t Skip This)

Now, put on a bra in your new size. The band should stay level, not ride up like a rebellious teenager. The center gore (the part between the cups) should lie flat against your sternum—no gaps, no hovering.

Lean forward. If your boobs spill out like they’re trying to escape a crowded subway, go up a cup size. If the straps leave trenches in your shoulders, the band is too loose—tighten the band, not the straps. Straps are for support, not a tug-of-war.

Common Mistakes (And How to Laugh Them Off)

Mistake #1: Measuring over an existing bra. That’s like measuring a tent while it’s still pitched. Do yourself a favor: go topless. Mistake #2: using the wrong tape. A carpenter’s tape? No. That’s for wood, not you. Mistake #3: giving up after one try. Sizing is a journey, not a test.

When To Remeasure

Life changes, and so do your boobs. Remeasure after weight shifts, pregnancy, or starting a new workout routine. Also? Every six months. Bras stretch, bodies evolve, and you deserve to feel amazing in your own skin.

Don’t trust that ancient bra from 2019. It’s time to let go, like your high school mixtape collection. You’ve grown.

The Final Cheerleading Speech

Here’s the beautiful truth: bra sizes are just numbers and letters. They don’t define your beauty, your shape, or your awesomeness. The perfect bra is the one that makes you forget you’re wearing one.

So go ahead—grab that measuring tape, do the math, and maybe even twirl in the mirror when you find your size. You deserve to feel as incredible as you already are. And if all else fails? Wear a bralette and a smile. You’ve got this, superstar.