Bra Size Calculator

What This Calculator Does

The Bra Size Calculator is a user-friendly online tool designed to help you accurately determine your ideal bra size based on your body measurements. By guiding you through the process of measuring yourself and applying standardized sizing methodology, this calculator aims to eliminate guesswork and ensure greater comfort and confidence in your daily wear. Whether you are shopping for a new bra, experiencing discomfort with your current size, or simply curious about your true fit, this calculator provides fast, reliable results tailored to your needs.

How to Use This Calculator

1. Gather a Soft Measuring Tape: To get the most accurate results, use a flexible, soft tape measure. Make sure you are wearing a well-fitting, non-padded bra or no bra for the most precise measurement.
2. Measure Your Band Size: Wrap the tape measure around your rib cage, directly under your bust. Ensure the tape is level and snug but not tight. Note the measurement in inches or centimeters.
3. Measure Your Bust Size: Place the tape measure around the fullest part of your bust, keeping it level across your back and front. Make sure the tape is not compressing your bust. Record this measurement.
4. Enter Your Measurements: Input your band and bust measurements into the calculator fields.
5. View Your Results: The calculator will instantly display your recommended bra size, including the band and cup size, enabling you to shop or adjust your fit accordingly.

Definitions of Key Terms

Bra Size

The standardized size representing the combination of your band size (numeric) and cup size (alphabetical), such as 34B or 36C. This is the result you use when shopping for bras.

Band Size

The numeric component of your bra size, representing the measurement around your rib cage just beneath your bust. Common sizes include 32, 34, 36, etc.

Cup Size

The alphabetical component of your bra size, reflecting the difference between your band and bust measurements. Examples include A, B, C, D, etc.

Bust Measurement

The circumference around the fullest part of your bust, measured in inches or centimeters.

Underbust Measurement

The circumference measured directly underneath your breasts, around your rib cage. This is used to determine your band size.

Calculation Methodology

The Bra Size Calculator uses internationally recognized sizing formulas to derive your band and cup size from your measurements. The calculation involves a few simple steps that convert your raw measurements into a standard size format.

Measure underbust (band) in inches

If the underbust measurement is an even number, add 4 to get your band size
If the underbust measurement is an odd number, add 5 to get your band size

Measure bust at fullest part in inches

Cup size = Bust measurement minus band size

Match cup size difference to cup letter:
0 inch difference = AA
1 inch difference = A
2 inch difference = B
3 inch difference = C
4 inch difference = D
5 inch difference = DD/E
6 inch difference = DDD/F
(Continue pattern for larger sizes)

Bra Size = Band Size + Cup Letter

For example, if your underbust measures 32 inches and your bust measures 35 inches:
1. Add 4 to 32 (since it is even) for a band size of 36.
2. The difference between bust and band is 35 - 36 = -1. In this case, round up to the next closest cup size if negative or measure again for accuracy.
3. Use the difference to select your cup size. A 1-inch difference is an A cup.
4. Your bra size would be 36A.

Practical Scenarios

• Shopping for a New Bra: You are in a store or shopping online but uncertain of your current size. Use the calculator to determine your accurate bra size before making a purchase, ensuring a comfortable and supportive fit.
• Experiencing Discomfort or Poor Fit: If your current bras feel too tight, loose, or cause irritation, use the calculator to double-check your measurements and update your preferred size.
• Body Changes Due to Weight Fluctuations or Pregnancy: After significant weight loss, gain, or post-pregnancy, your body shape may have changed. The calculator helps you adapt to these changes by recalculating your ideal size.
• Assisting a Friend or Family Member: When helping someone else select a bra or teaching a teen about proper fit, the calculator provides a simple, objective way to determine the correct size together.

Advanced Tips & Best Practices

• Measure at the Right Time: Take your measurements at the end of the day, when your body is at its most relaxed and natural state. Avoid measuring during your menstrual cycle when breast size can temporarily increase.
• Check Your Fit Regularly: Reassess your bra size every 6-12 months, especially after changes in weight, pregnancy, or significant shifts in physical activity. Bodies change over time, and so can your ideal fit.
• Be Aware of Brand Differences: Not all brands use identical sizing standards. Use the calculator as a starting point, but always refer to the sizing chart provided by the specific manufacturer.
• Double-Check Measurements: For best results, repeat each measurement two to three times and average the results. Small inaccuracies can lead to an uncomfortable fit.
• Understand Sister Sizing: If you cannot find your exact calculated size, try a sister size (going up a band size and down a cup size, or vice versa) for a similar fit.

Frequently Asked Questions (Optional)

Why do my measurements sometimes give different results than the bra size I usually wear?

Your body shape, the style and brand of the bra, and even how tightly you measure can all influence results. Use the calculator as a guide, but also focus on comfort and support. Trying on a few sizes can help you find the best fit.

What if my band size or cup size falls between standard sizes?

If your measured size does not match standard sizing exactly, try the nearest sister size or adjust the fit based on comfort. Many brands offer extended or in-between sizes as well.

How often should I re-measure my bra size?

It is a good idea to re-measure every 6-12 months or after any significant body change, such as weight fluctuations, pregnancy, or surgery. Regular measurement helps you stay comfortable and supported.