Bra Size Calculator

- May 09, 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, 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 centimetres 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 centre 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.

Why Use a Bra Size Calculator?

Finding the right bra size can be tricky. A bra that fits well can make a huge difference in comfort and support. With our Bra Size Calculator, you’ll get accurate results based on your measurements. This tool helps you avoid the guesswork and ensures you find a size that feels just right for you.

How to Measure for Your Size

To get the best results from the Bra Size Calculator, it’s vital to take accurate measurements. Here’s how you can do it:

  • Wear a non-padded bra or no bra for true measurements.
  • Measure under your bust for the band size, keeping the tape snug.
  • Measure around the fullest part of your bust for the cup size.
  • Stand straight and relax your arms at your sides while measuring.
  • Double-check each measurement for accuracy.

Selecting Your Measurement System

Our calculator allows you to choose between different measurement systems. You can use inches, commonly used in the US and UK, or centimetres used in Europe. Make sure to select the one that suits you best to gain accurate results tailored to your region.

Customising Your Preferences

The calculator also considers your personal preferences. You can specify your body frame, breast shape, and fitting preferences. These details help refine your size recommendation and ensure a better fit according to your unique body type.

Understanding Bra Size Basics

Bra sizes consist of two parts: the band size and the cup size. The band size is the number that represents the measurement around your ribcage. The cup size is a letter that indicates the difference between your band and bust measurements. Knowing these basics can help you understand how to choose the right bra.

Learning About Sister Sizes

Sister sizes can be a helpful concept to know. These sizes have the same cup volume but different band sizes. For example, if your recommended size is 34C, you might also try 32D or 36B for a better fit if needed. This can be a great option if your size isn’t as comfortable as you’d like.

International Size Equivalents

Different countries follow various sizing systems. For instance, the US and UK typically use inches, while Europe uses centimetres. Knowing this can help you convert your size if you’re shopping internationally. Our calculator can provide these equivalents based on your measurements, making it easier to find the right fit wherever you are.

Common Fit Issues and Solutions

Wearing the right bra size can help avoid common fit issues. Here are a few signs that your bra may not fit well:

  • The band rides up your back.
  • The cups overflow or have gaps.
  • The straps dig into your shoulders or slip off.
  • The centre gore does not sit flat against your chest.

If you notice any of these problems, it may be time to measure again and find a new size with our calculator.