When shipping packages, carriers like UPS often use dimensional weight (also known as volumetric weight or DIM weight) to calculate shipping costs. This is particularly important for lighter packages that take up a lot of space. UPS, like most carriers, charges based on whichever is greater: the actual weight of the package or its dimensional weight.
How is Dimensional Weight Calculated?
The formula for calculating dimensional weight is as follows:
Dimensional Weight = (Length x Width x Height) / Divisor
Length, Width, and Height: These are the outside dimensions of your package, typically measured in inches. It's best practice to measure the longest side as Length, the next longest as Width, and the shortest side as Height.
Divisor: The divisor used by UPS can vary. Historically, common divisors have been 139 cubic inches per pound for international shipments and domestic shipments over certain weight thresholds, or 166 cubic inches per pound for other domestic shipments. As of recent updates, UPS often uses 139 for many domestic and international services. Always verify the current divisor with UPS for the specific service you are using.
Why is this Important for Shipping?
Understanding dimensional weight helps you:
Estimate shipping costs more accurately: Prevent surprises when billing.
Optimize packaging: Use appropriately sized boxes to minimize unnecessary shipping charges, especially for light but bulky items.
Compare shipping options: Different services or carriers might have different DIM weight divisors, affecting the final cost.
How to Use This Calculator
Simply enter the Length, Width, and Height of your package in inches, along with its Actual Weight in pounds. The calculator will then determine the dimensional weight and compare it to the actual weight, showing you the billable weight UPS will use.
function calculateDimensionalWeight() {
var length = parseFloat(document.getElementById("length").value);
var width = parseFloat(document.getElementById("width").value);
var height = parseFloat(document.getElementById("height").value);
var actualWeight = parseFloat(document.getElementById("actualWeight").value);
var resultDiv = document.getElementById("result");
// Validate inputs
if (isNaN(length) || isNaN(width) || isNaN(height) || isNaN(actualWeight) ||
length <= 0 || width <= 0 || height <= 0 || actualWeight <= 0) {
resultDiv.innerHTML = 'Please enter valid positive numbers for all fields.';
resultDiv.style.backgroundColor = "#dc3545"; // Red for error
return;
}
// UPS divisor (commonly 139, but can vary by service. Verify with UPS.)
var divisor = 139;
var dimensionalWeight = (length * width * height) / divisor;
// Determine the billable weight
var billableWeight = Math.max(actualWeight, dimensionalWeight);
resultDiv.innerHTML = 'Billable Weight: ' + billableWeight.toFixed(2) + ' lb';
resultDiv.style.backgroundColor = "#28a745"; // Green for success
}