Quick Answer

To determine your correct bra size at home, measure your band size by wrapping a tape measure snugly around your ribcage, then measure your bust at the fullest part. Subtract the band measurement from the bust measurement to find your cup size. Use a bra size calculator or chart to confirm, and always try on bras to verify the fit.

Finding your correct bra size doesn't require a professional fitting. With a soft tape measure and a few minutes, you can measure yourself at home and get a solid starting point for ordering bras online. This guide walks you through the process step by step, including common mistakes to avoid.

Accurate measurements are especially important when shopping for pullover styles like bandeaus and full-coverage bras, where the band and cup work together for support. Whether you're between sizes or have changed shape recently, these steps will help you find a bra that feels as good as it looks.

What You Need to Measure Your Bra Size

Gather a soft measuring tape (the kind used for sewing), a mirror, and wear a non-padded bra or no bra at all. Stand straight with your arms relaxed at your sides, and make sure the tape is level around your body. If you don't have a tape, use a piece of string and a ruler.

Measure twice to ensure accuracy, as even a half-inch difference can affect your cup size. Keep in mind that your measurements may change with weight fluctuations, exercise, or hormonal cycles, so re-measure every few months or when a bra starts to feel off.

Step-by-Step: How to Measure Your Band and Bust

First, measure your band size. Wrap the tape snugly around your ribcage, just under your bust. The tape should be parallel to the floor and tight enough that it doesn't slide, but not digging in. Round to the nearest whole number. If the number is even, add 4 inches; if odd, add 5. This is your band size.

Next, measure your bust. Wrap the tape around the fullest part of your chest, keeping it level and not too tight. Round to the nearest whole number. Subtract your band size from this bust measurement. The difference in inches corresponds to your cup size: 1 inch = A, 2 = B, 3 = C, 4 = D, 5 = DD/E, and so on.

For example, if your band measurement is 34 inches and your bust is 37 inches, the 3-inch difference suggests a C cup, so you'd be a 34C. Remember, this is a starting point; different styles and brands may fit differently.

  • Use a soft measuring tape, not a metal one, for accurate results.
  • Take measurements in front of a mirror to ensure the tape is level.

Common Mistakes to Avoid When Measuring Yourself

One common mistake is measuring over a padded bra, which adds extra inches to your bust and skews the result. Another is pulling the tape too tight or too loose—aim for a snug but comfortable fit. Also, don't slouch; stand up straight with your shoulders relaxed.

People often forget to re-measure after weight changes or pregnancy. Your bra size can change even without a significant weight shift, so it's wise to check every few months. Finally, don't rely solely on a calculator; use it as a guide and confirm with a physical try-on whenever possible.

Using a Bra Size Calculator and Charts

Many online bra size calculators can do the math for you, but they're only as accurate as your measurements. Use the same steps above, input your numbers, and note that different brands may have slightly different sizing charts. Always check the brand's specific guide before ordering.

For example, ARQ provides a bra size guide for its styles. The ZELDA BANDEAU suggests sizing down if you're between sizes, while the FULL-COVERAGE BRA recommends many people size up. These brand-specific notes are crucial for getting the right fit.

Step-by-Step: Measure Your Bra Size at Home

  1. Measure your band: Wrap the tape snugly around your ribcage, just under your bust. Ensure it's level and not too tight. Round to the nearest whole number, then add 4 if even, 5 if odd to get your band size. Checkpoint: The tape should be snug but not digging in. If it leaves red marks, it's too tight.
  2. Measure your bust: Wrap the tape around the fullest part of your chest, keeping it level and not compressing. Round to the nearest whole number. Checkpoint: Make sure the tape is not slipping down or pulling tight across your back.
  3. Calculate your cup size: Subtract your band size from your bust measurement. The difference in inches corresponds to your cup size (1=A, 2=B, 3=C, 4=D, 5=DD/E). Checkpoint: If the difference is a half-inch, round up to the next whole number.
  4. Confirm with a bra size calculator or chart: Use your numbers in an online calculator or the brand's size chart to confirm your size. Remember that different styles may fit differently. Checkpoint: Always read the brand's specific fit notes, like sizing up or down for certain styles.
  5. Try on and adjust: When your bra arrives, try it on. The band should be level and snug, and the cups should contain your breasts without spillage or gaps. Adjust straps as needed. Checkpoint: If the band rides up or the cups pucker, try a different size.

How ARQ Bras Fit: What to Know

  • ZELDA BANDEAU, gym: Classic bandeau shape with a dance inspired pinch-front detail. Use our bra size guide below when choosing which size to order. If between sizes, size down. 92% organic cotton, 8% spandex. Best fits US cup sizes A through F. This pullover style has no closures, so the band and fabric stretch must do the work. Sizing down if you're between sizes helps prevent the band from riding up.
  • FULL-COVERAGE BRA, porcini: The same details as our classic Wide-Strap Bra but with more fabric and a slightly different shape to accommodate for larger cup sizes. Signature bound edges. Pullover design. Best fits US cup sizes A through F. 92% organic cotton, 8% spandex. Many people size up from their usual size in this style. Because this style offers more coverage, it fits differently than a bandeau. If you're between sizes, sizing up can give a more comfortable fit without sacrificing support.

Measuring your bra size at home is simple and gives you a reliable starting point for online shopping. Remember that different styles and brands fit differently, so always consult the brand's size guide and be open to adjusting your size. With these steps, you'll find a bra that offers both comfort and support.