Step by Step Guide to Measure Lingerie Size

Let’s be real — finding the right lingerie size shouldn’t feel like solving a math equation. But if you’ve ever squeezed into a too-tight bra or dealt with constant slippage, you know most of us are wearing the wrong size. In fact, studies show that up to 80% of women wear the wrong bra size (University of Portsmouth, 2008). Yikes.

As a lingerie fit specialist who’s helped hundreds of clients ditch discomfort, I’m breaking down how to measure your lingerie size accurately — no guesswork needed.

Why Measuring Matters

The right fit isn’t just about comfort — it affects posture, confidence, and even back pain. Many brands use vanity sizing or inconsistent standards, so relying on labeled sizes is risky. Taking precise measurements ensures you’re shopping smarter.

What You’ll Need

• A soft measuring tape (the kind used for sewing)
• Minimal clothing (a fitted t-shirt or none at all)
• Notepad or phone to record numbers

Step 1: Measure Your Band Size

Wrap the tape snugly around your ribcage, just under your bust. Keep it parallel to the floor. Don’t suck in! Round to the nearest whole inch.

• If the number is even: add 4 inches
• If odd: add 5 inches

Example: 31" underbust → 31 + 5 = 36 → Band size: 36

Step 2: Measure Your Bust Size

Loosen the tape and wrap it around the fullest part of your bust (usually nipple level). Keep it level and don’t pull too tight. Record the measurement.

Step 3: Calculate Cup Size

Subtract your band size from your bust size. Each inch equals one cup size.

So if your bust is 39" and your band is 36", the difference is 3" → C cup.

Pro Tips for Accuracy

• Measure in the evening — breasts can swell slightly throughout the day
• Try on bras with a properly measured lingerie size as a starting point, but always check fit
• Remember: band should provide 80% of support, not straps

One of my favorite tricks? The lean-forward method: bend forward 90 degrees when fastening your bra — this lets gravity fill the cups naturally, reducing spillage.

When to Re-Measure

Life changes affect fit. Re-measure after:

• Weight loss/gain of 10+ lbs
• Pregnancy or breastfeeding
• Every 6 months, even if nothing changes

Brands vary widely. For example, a 34C at Victoria’s Secret might fit like a 36B at Wacoal. That’s why knowing your true lingerie size guide is power.

Final Thoughts

Measuring your lingerie size isn’t rocket science — it’s self-care. With accurate numbers, you’ll shop with confidence, save money on returns, and finally feel supported — literally.