Bra Size Calculator

Category: Other Health
- March 21, 2025
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Find your perfect bra size with this calculator. Accurate measurements lead to better comfort and support. For best results, measure while wearing a non-padded bra or no bra.

Measurement System

Your Measurements

Band Size Measurement Full Bust Measurement Measure directly under bust, keeping tape snug and level Measure around the fullest part of your bust Tips for Accurate Measurements: • Stand straight with arms relaxed at sides • Keep measuring tape parallel to the floor
How to Take Accurate Measurements
  1. Wear a non-padded bra or no bra for the most accurate measurements.
  2. Band/Underbust: Measure directly under your bust where a bra band would sit. Keep the tape measure snug and parallel to the ground.
  3. Full Bust: Measure around the fullest part of your bust (typically at nipple level). Keep the tape measure parallel to the ground.
  4. Stand straight with your arms relaxed at your sides during both measurements.
  5. Take each measurement twice to confirm accuracy.
inches
Measure directly under your bust, making sure the tape measure is snug and level all the way around.
inches
Measure around the fullest part of your bust, keeping the tape measure parallel to the floor.

Additional Factors

Fitting Preferences

Advanced Options

Understanding Bra Sizing

Bra sizes consist of a band size (number) and a cup size (letter). The band size indicates the measurement around your ribcage, while the cup size represents the difference between your band and bust measurements.

How Bra Sizing Works

Bra sizing varies by region, but generally follows these principles:

  • Band Size: Usually derived from your underbust measurement, possibly with some adjustment.
  • Cup Size: Calculated from the difference between your full bust and band measurements.
Sister Sizes

Sister sizes have the same cup volume but different band sizes. For example, 34C, A 32D, and 36B are all sister sizes. This is useful when you need to adjust the band size without changing the cup volume.

International Sizing

Different countries use different sizing systems:

  • US/UK: Uses inches for measurements and cup sizes AA, A, B, C, D, DD, etc.
  • EU: Uses centimeters and cup sizes A, B, C, D, E, F, etc.
  • France: Similar to EU but with different cup progressions.
  • Italy: Uses numbers for both band and cup (e.g., 1, 2, 3, 4).
Signs of a Good Fit

A properly fitting bra should have the following characteristics:

  • The band sits parallel to the floor and feels snug but not tight.
  • The center gore (the part between the cups) sits flat against your sternum.
  • The cups fully contain your breast tissue without any spillage or gaps.
  • The straps don't dig into your shoulders or fall down.
  • The wire (if present) sits at the base of your breast and follows your natural contour.
Measuring Tips
  • Measure yourself while wearing a non-padded bra or no bra.
  • Keep the measuring tape parallel to the floor.
  • For the most accurate results, have someone help you measure.
  • Take measurements twice to confirm accuracy.
  • Remember that bra sizing is just a starting point - always try on bras before purchasing.

What Is the Bra Size Calculator?

The Bra Size Calculator is a tool that helps you determine your ideal bra size based on your underbust and full bust measurements. By combining this data with your region, body frame, and preferences, it provides a recommended size, alternative "sister sizes," international equivalents, and fitting advice.

Formula Used for Bra Sizing

Band Size: Rounded or adjusted value based on underbust measurement and region.

Cup Size: Difference between full bust and band measurements.

Example: If Full Bust = 36", Underbust = 32"

Cup Difference = 36 - 32 = 4 inches → Cup Size = D

Resulting Bra Size = 32D

How to Use the Calculator

  1. Select your preferred measurement system: Inches (US/UK) or Centimeters (EU).
  2. Measure your underbust (band size) and full bust using a flexible measuring tape.
  3. Enter the measurements into the respective fields.
  4. Choose your sizing region and optionally provide your current bra size.
  5. Adjust any body frame or breast shape options for more accurate results.
  6. Select your preferred fit for band and cup if applicable.
  7. Click the "Calculate My Size" button.
  8. Review your recommended size, sister sizes, and international equivalents.

Why This Calculator Is Useful

Wearing the right bra size can significantly impact comfort, posture, and appearance. This calculator is useful because it:

  • Provides a reliable size based on your unique body measurements.
  • Supports international sizing, making shopping easier worldwide.
  • Accounts for preferences and body variations such as frame and breast shape.
  • Suggests sister sizes in case your exact size is unavailable.
  • Offers style recommendations to help you find bras that suit your shape and needs.

FAQs

1. What if my bust measurement is smaller than my underbust?
This usually indicates an input error. Your bust measurement should be larger for the calculator to work correctly.

2. Can I use this if I’m in between sizes?
Yes, the calculator accounts for small variations and provides sister sizes that offer similar fit with slight adjustments.

3. Does it work for all regions?
Yes, the calculator includes support for US, UK, EU, Australia/NZ, France, Italy, and Japan sizing systems.

4. Should I measure in inches or centimeters?
You can use either. Choose the system you’re most comfortable with, or the one used in your shopping region.

5. How accurate are the results?
The results are a great starting point. Fit can vary by brand, style, and body shape, so always try on before purchasing when possible.

Helpful Tips

  • Measure while wearing a non-padded bra or no bra.
  • Keep the tape snug but not tight and parallel to the ground.
  • Take measurements more than once to confirm consistency.
  • Use the results as a guide, but also trust your comfort when trying on bras.