Bra Size Guide Calculator

Use this calculator to estimate your bra size based on your measurements. For best results, wear a non-padded bra or no bra when measuring.

Snug Underbust Measurement (inches): Measure snugly around your rib cage, directly under your bust.

Fullest Bust Measurement (inches): Measure around the fullest part of your bust, keeping the tape level.

Understanding Bra Sizing

Finding the right bra size is crucial for comfort, support, and the overall look of your clothing. A well-fitting bra can alleviate back and shoulder pain, improve posture, and enhance your silhouette. Unfortunately, many women wear the wrong size, often due to outdated measurement methods or inconsistencies between brands.

How to Measure Accurately

To get the most accurate measurements for this calculator, follow these steps:

Underbust Measurement (Band Size): Stand upright and wrap a soft measuring tape snugly around your rib cage, directly under your bust. Make sure the tape is level all the way around and exhale to get the smallest measurement. This measurement helps determine your band size.
Fullest Bust Measurement (Cup Size): While still standing, wrap the measuring tape around the fullest part of your bust (usually across the nipples). Ensure the tape is level and not too tight or too loose. This measurement, in conjunction with your band size, helps determine your cup size.

It's best to take these measurements while wearing a non-padded bra or no bra at all to avoid adding extra inches.

The Calculation Method Explained

This calculator uses a common modern sizing method:

Band Size: Your snug underbust measurement is rounded to the nearest whole inch. If the rounded number is odd, we add one inch to make it an even number. This even number is your estimated band size (e.g., 30, 32, 34).
Cup Size: The difference between your fullest bust measurement and your calculated band size determines your cup size. Each inch of difference corresponds to a specific cup letter:
- Less than 1 inch: AA
- 1 inch: A
- 2 inches: B
- 3 inches: C
- 4 inches: D
- 5 inches: DD (or E)
- 6 inches: DDD (or F)
- 7 inches: G
- 8 inches: H
- 9 inches: I
- 10 inches: J

Important Considerations

While this calculator provides a good starting point, remember that bra sizing is not an exact science. Factors like breast shape, brand variations, and personal preference can influence the perfect fit. Always try on bras before purchasing, and don't be afraid to try "sister sizes" (e.g., if you're a 34C, a 32D or 36B might also fit).

This calculator is a guide to help you narrow down your options and understand your body better. Happy bra shopping!

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