Abrathatfits Calculator

ABraThatFits Calculator

Use this calculator to find your recommended bra size based on the popular r/ABraThatFits measurement method. Accurate measurements are key!

Inches Centimeters

Measure comfortably, not too tight, not too loose.

Measure tightly, exhaling all air. This is crucial for band size.

As tight as possible, exhaling all air. This helps confirm band size.

Measure around the fullest part of your bust while standing upright.

Lean forward 90 degrees and measure around the fullest part of your bust.

Lie flat on your back and measure around the fullest part of your bust.

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Please re-check your measurements carefully."; return; } // Step 4: Determine Cup Letter (UK Sizing) var cupLettersUK = ["AA", "A", "B", "C", "D", "DD", "E", "F", "FF", "G", "GG", "H", "HH", "J", "JJ", "K", "KK", "L", "LL", "M", "MM", "N", "NN", "O", "OO", "P", "PP", "Q", "QQ", "R", "RR", "S", "SS", "T", "TT", "U", "UU", "V", "VV", "W", "WW", "X", "XX", "Y", "YY", "Z", "ZZ"]; var cupIndex = Math.floor(cupDifference); if (cupIndex = cupLettersUK.length) { resultDiv.innerHTML = "Your measurements suggest a cup size larger than this calculator can determine. Please consult a professional fitter."; return; } var cupSize = cupLettersUK[cupIndex]; var recommendedSize = bandSize + cupSize; // Step 5: Calculate Sister Sizes var sisterSizes = []; // One band size down, one cup size up if (bandSize >= 30) { // Ensure band doesn't go below common minimum var smallerBand = bandSize – 2; var smallerBandCupIndex = cupIndex + 1; if (smallerBandCupIndex = 0) { sisterSizes.push(largerBand + cupLettersUK[largerBandCupIndex]); } // Display Results var resultHTML = "

Your Recommended Bra Size (UK Sizing)

"; resultHTML += "Based on your measurements, your estimated bra size is: " + recommendedSize + ""; resultHTML += "This is a starting point. Bra fit can vary greatly between brands and styles."; resultHTML += "Detailed Breakdown:"; resultHTML += "
    "; resultHTML += "
  • Calculated Band Size: " + bandSize + " inches
  • "; resultHTML += "
  • Average Bust Measurement: " + averageBust.toFixed(1) + " inches
  • "; resultHTML += "
  • Cup Difference: " + cupDifference.toFixed(1) + " inches
  • "; resultHTML += "
"; if (sisterSizes.length > 0) { resultHTML += "Sister Sizes to Try: " + sisterSizes.join(", ") + ""; resultHTML += "Sister sizes have the same cup volume but a different band size. If your recommended band feels too tight or too loose, try a sister size."; } else { resultHTML += "No common sister sizes could be calculated for your measurements."; } resultHTML += "Important Considerations:"; resultHTML += "
    "; resultHTML += "
  • Your snug underbust is " + snugUnderbust.toFixed(1) + " inches. Your band size (" + bandSize + ") should feel snug and supportive.
  • "; resultHTML += "
  • Your loose underbust is " + looseUnderbust.toFixed(1) + " inches. If your band feels too tight, compare it to this measurement.
  • "; resultHTML += "
  • Your tight underbust is " + tightUnderbust.toFixed(1) + " inches. Your band should not feel tighter than this.
  • "; resultHTML += "
  • Your bust measurements (Standing: " + standingBust.toFixed(1) + ", Leaning: " + leaningBust.toFixed(1) + ", Lying: " + lyingBust.toFixed(1) + ") were averaged to determine cup size.
  • "; resultHTML += "
"; resultHTML += "Remember, this is a guide. The best way to find your perfect fit is to try on bras!"; resultDiv.innerHTML = resultHTML; }

Understanding the ABraThatFits Method for Your Perfect Bra Size

Finding a well-fitting bra can be a transformative experience, offering comfort, support, and a boost in confidence. Unfortunately, many people wear the wrong bra size, leading to discomfort, poor posture, and an unflattering silhouette. The "ABraThatFits" method, popularized by the online community r/ABraThatFits, provides a comprehensive approach to measuring yourself for a bra, aiming for a more accurate starting point than traditional methods.

Why Traditional Bra Sizing Often Fails

Traditional bra sizing often relies on adding 4 inches to your underbust measurement to determine band size, and then a single bust measurement for cup size. This method is outdated and frequently leads to ill-fitting bras, typically with a band that is too loose and cups that are too small. The ABraThatFits method, in contrast, uses multiple measurements to account for individual body variations and breast tissue distribution.

How to Take Your Measurements Accurately

For the most accurate results from this calculator, it's crucial to take your measurements correctly. Use a soft measuring tape and wear a non-padded, unlined bra or no bra at all. Ensure the tape is parallel to the floor and snug against your skin without digging in.

  1. Loose Underbust: Measure around your ribcage directly under your bust, where a bra band would sit. The tape should be snug but comfortable, not tight.
  2. Snug Underbust: Measure again in the same spot, but pull the tape tighter, exhaling all air from your lungs. This measurement is critical for determining your band size.
  3. Tight Underbust: Pull the tape as tight as you possibly can, exhaling completely. This helps confirm the firmness of your band.
  4. Standing Bust: Stand upright and measure around the fullest part of your bust, typically at nipple level. Ensure the tape is parallel to the floor.
  5. Leaning Bust: Lean forward 90 degrees (parallel to the floor) and measure around the fullest part of your bust. This helps capture breast tissue that might fall differently when unsupported.
  6. Lying Bust: Lie flat on your back and measure around the fullest part of your bust. This helps account for breast tissue that spreads out when lying down.

How the ABraThatFits Calculator Works

This calculator uses your six measurements to determine your recommended UK bra size:

  • Band Size: Your band size is primarily derived from your snug underbust measurement, rounded to the nearest even number. A snug band is essential for support.
  • Cup Size: Your cup size is determined by the difference between your calculated band size and the average of your three bust measurements (standing, leaning, and lying). Each inch of difference corresponds to a specific UK cup letter (e.g., 1 inch = A, 2 inches = B, 3 inches = C, 4 inches = D, 5 inches = DD, 6 inches = E, etc.).

Understanding Sister Sizes

Sister sizes are bra sizes that have the same cup volume but a different band size. For every band size you go down, you go up one cup size, and vice-versa. For example, if your calculated size is 32DD, its sister sizes would be 30E (smaller band, larger cup letter) and 34D (larger band, smaller cup letter). Knowing your sister sizes can be incredibly helpful if your recommended band size feels slightly off, as it allows you to adjust the fit without changing the overall cup volume.

Important Considerations and Next Steps

While this calculator provides an excellent starting point, it's important to remember that it's a guide, not a definitive answer. Bra fit can be influenced by breast shape, brand variations, and personal preference. Always try on bras to confirm the fit. Look for a band that is snug and parallel to the floor, cups that fully encapsulate your breast tissue without gaping or spilling, and straps that provide support without digging in.

Use this calculator as your first step towards finding bras that truly fit and support you!

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