Finding the perfect bra size is crucial for comfort, support, and confidence. While many believe bra sizing is complex, it primarily relies on two key measurements: your underbust (band size) and your overbust (bust fullness). This calculator simplifies the process by using these measurements to suggest a standard bra size, commonly used by brands like Victoria's Secret.
How the Calculator Works
The calculation involves two main steps:
Band Size Determination: Your underbust measurement is the primary factor for your band size. If your underbust measurement is an even number (e.g., 32 inches), that's often your starting band size. If it's an odd number (e.g., 33 inches), you typically round up to the next even number (34 inches). This calculator takes your input and finds the nearest even number for the band.
Cup Size Determination: The cup size is derived from the difference between your overbust (fullest part of your bust) and your underbust measurement. The difference, when translated into inches, corresponds to a specific cup letter:
1 inch difference = A cup
2 inch difference = B cup
3 inch difference = C cup
4 inch difference = D cup
5 inch difference = DD (or E) cup
And so on, typically increasing by one letter for each additional inch.
This calculator calculates this difference and converts it to a suggested cup size.
Example Calculation
Let's say you measure:
Underbust (Band): 31.8 inches
Overbust (Bust Fullness): 36.5 inches
Step 1: Band Size
Your underbust is 31.8 inches. Rounded up to the nearest even number, this suggests a band size of 32.
Step 2: Cup Size
The difference between your overbust and underbust is: 36.5 inches – 31.8 inches = 4.7 inches.
This difference is closest to 4 inches, which typically corresponds to a D cup.
Therefore, based on these measurements, your estimated bra size would be 32D.
Important Considerations
Bra sizing can vary slightly between brands and even styles within the same brand. Victoria's Secret, like other lingerie retailers, has its own sizing nuances. This calculator provides a strong starting point, but it's always recommended to:
Try on bras to ensure the best fit.
Consult a professional bra fitter for the most accurate assessment.
Consider different styles (e.g., plunge, push-up, full coverage) as they can fit differently.
Using accurate measurements and understanding the basic principles of bra sizing will significantly improve your chances of finding a bra that fits comfortably and provides excellent support.
function calculateBraSize() {
// Clear previous errors and results
document.getElementById("result").style.display = "none";
document.getElementById("bandUnderbustError").innerText = "";
document.getElementById("bandUnderbustError").style.display = "none";
document.getElementById("bustFullnessError").innerText = "";
document.getElementById("bustFullnessError").style.display = "none";
// Get input values
var bandUnderbustInput = document.getElementById("bandUnderbust").value;
var bustFullnessInput = document.getElementById("bustFullness").value;
// Validate inputs
var bandUnderbust = parseFloat(bandUnderbustInput);
var bustFullness = parseFloat(bustFullnessInput);
var errors = false;
if (isNaN(bandUnderbust) || bandUnderbust <= 0) {
document.getElementById("bandUnderbustError").innerText = "Please enter a valid positive number for your underbust measurement.";
document.getElementById("bandUnderbustError").style.display = "block";
errors = true;
}
if (isNaN(bustFullness) || bustFullness <= 0) {
document.getElementById("bustFullnessError").innerText = "Please enter a valid positive number for your overbust measurement.";
document.getElementById("bustFullnessError").style.display = "block";
errors = true;
}
if (bustFullness <= bandUnderbust) {
document.getElementById("bustFullnessError").innerText = "Overbust measurement must be greater than underbust measurement.";
document.getElementById("bustFullnessError").style.display = "block";
errors = true;
}
if (errors) {
return; // Stop calculation if there are validation errors
}
// Calculate Band Size
var calculatedBandSize;
if (bandUnderbust % 2 === 0) {
calculatedBandSize = bandUnderbust;
} else {
// Round up to the nearest even number
calculatedBandSize = Math.ceil(bandUnderbust);
if (calculatedBandSize % 2 !== 0) {
calculatedBandSize = calculatedBandSize + 1;
}
}
// Ensure band size isn't ridiculously small (e.g., user enters 1 inch)
if (calculatedBandSize 44) calculatedBandSize = 44; // Arbitrary upper limit for common sizing
// Calculate Cup Size
var cupDifference = bustFullness – bandUnderbust;
var cupSize = "";
if (cupDifference >= 1 && cupDifference = 2 && cupDifference = 3 && cupDifference = 4 && cupDifference = 5 && cupDifference = 6 && cupDifference = 7 && cupDifference = 8) {
// For very large differences, can extend or note it's beyond typical ranges
cupSize = "H+ (Check Brand Specifics)";
} else {
// For differences less than 1 inch (unusual but possible)
cupSize = "AA (Check Fit)";
}
// Display the result
var resultElement = document.getElementById("result");
resultElement.innerHTML = 'Estimated Bra Size: ' + calculatedBandSize + cupSize;
resultElement.style.display = "block";
}