Usps Shipping Cost Calculator by Weight

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Calculate your USPS postage costs accurately and easily based on package weight.

Shipping Cost Calculator

What is the USPS Shipping Cost Calculator by Weight?

The USPS Shipping Cost Calculator by Weight is an essential online tool designed to help individuals and businesses accurately estimate the postage costs for sending packages via the United States Postal Service (USPS). This calculator simplifies the often complex pricing structure of USPS services by allowing users to input key details about their shipment, most importantly, the total weight of the package. By providing this information, users can quickly determine the likely cost for various USPS shipping options, such as First-Class Package Service, Priority Mail, and USPS Ground Advantage. This tool is invaluable for budgeting shipping expenses, comparing service levels, and ensuring customers receive accurate shipping quotes. Anyone who regularly sends packages, from small online retailers to individuals mailing gifts, can benefit from using a USPS shipping cost calculator by weight.

A common misconception is that weight is the *only* factor determining shipping cost. While weight is a primary determinant, other factors like package dimensions (affecting dimensional weight), destination ZIP code (distance and zone), shipping service chosen, and any special handling or insurance needs significantly impact the final price. This USPS shipping cost calculator by weight attempts to factor in these variables for a more realistic estimate.

USPS Shipping Cost Calculation Formula and Mathematical Explanation

Calculating USPS shipping costs involves several factors, with weight being primary, but also considering package dimensions, service type, and distance. The core principle is determining the greater of the actual weight or the dimensional weight, and then applying the price structure for the selected service.

Step-by-Step Calculation Process:

1. Determine Actual Weight: This is the straightforward weight of the package.
2. Calculate Dimensional Weight (if applicable): For certain services and larger packages, USPS uses dimensional weight (DIM weight). The formula is:
   DIM Weight = (Length × Width × Height) / Divisor
   The divisor varies by service and USPS policies (commonly 166 or 194). If the DIM weight is greater than the actual weight, USPS charges based on the DIM weight.
3. Identify the Greater Weight: Compare the Actual Weight and the Dimensional Weight. The higher of the two is used for pricing.
4. Determine Shipping Zone: Based on the origin and destination ZIP codes, USPS assigns a shipping zone. Longer distances correspond to higher zones.
5. Select Shipping Service and Pricing: Each USPS service (First-Class Package, Priority Mail, etc.) has its own price chart based on the greater weight (actual or DIM) and the shipping zone.
6. Add Ancillary Services: Costs for services like insurance, signature confirmation, or special handling are added if selected.

Variable Explanations:

USPS Shipping Cost Variables

Variable	Meaning	Unit	Typical Range / Notes
Package Weight (Actual)	The measured weight of the package.	Pounds (lbs)	0.1 lbs to 70 lbs (max for most services)
Package Length	The longest dimension of the package.	Inches (in)	1 to 108 inches (max for length + girth)
Package Width	The dimension perpendicular to length.	Inches (in)	1 to 108 inches (max for length + girth)
Package Height	The dimension perpendicular to length and width.	Inches (in)	1 to 108 inches (max for length + girth)
Dimensional Divisor	A factor used to calculate dimensional weight.	Varies (e.g., 166, 194)	Depends on service and USPS rules. Essential for large, light items.
Dimensional Weight	Calculated weight based on package size.	Pounds (lbs)	Calculated: (L*W*H)/Divisor. Can exceed actual weight.
Destination ZIP Code	The 5-digit postal code of the delivery address.	N/A	Used to determine shipping zones.
Shipping Service	The chosen USPS delivery speed and type.	N/A	First-Class, Priority, Ground Advantage, Express, etc.
Estimated Cost	The final calculated postage price.	USD ($)	Varies widely based on all factors.

Practical Examples (Real-World Use Cases)

Example 1: Small Online Retailer Shipping a Lightweight Item

Scenario: Sarah runs an Etsy shop selling handmade jewelry. She needs to ship a small, lightweight necklace to a customer in California from New York.

• Package Weight: 0.3 lbs
• Package Dimensions: 6″ x 4″ x 2″
• Shipping Service: First-Class Package Service
• Destination ZIP Code: 90210 (Zone 8 from NY)

Calculation:

• Actual Weight: 0.3 lbs
• Dimensional Weight: (6 * 4 * 2) / 166 = 48 / 166 ≈ 0.29 lbs
• Greater Weight: 0.3 lbs (Actual weight is greater)
• Service: First-Class Package Service
• Zone: 8

Estimated Cost: Using the USPS rate chart for First-Class Package Service, Zone 8, up to 0.5 lbs, the cost might be around $5.25 (Note: Actual rates vary and are subject to change).

Interpretation: For small, light items, actual weight is usually the determining factor. First-Class Package Service is cost-effective for these shipments.

Example 2: Business Shipping a Slightly Heavier, Larger Box

Scenario: A company is shipping a product catalog to a client in another state.

• Package Weight: 5 lbs
• Package Dimensions: 12″ x 10″ x 10″
• Shipping Service: USPS Ground Advantage
• Destination ZIP Code: 60601 (Zone 5 from assumed origin)

Calculation:

• Actual Weight: 5 lbs
• Dimensional Weight: (12 * 10 * 10) / 166 = 1200 / 166 ≈ 7.23 lbs
• Greater Weight: 7.23 lbs (Dimensional weight is greater)
• Service: USPS Ground Advantage
• Zone: 5

Estimated Cost: USPS Ground Advantage pricing for Zone 5, between 5 lbs and 10 lbs (using dimensional weight), might be approximately $18.50 (Note: Actual rates vary).

Interpretation: This example highlights how dimensional weight can increase shipping costs for packages that are large relative to their weight. Choosing the right service like USPS Ground Advantage is crucial for cost savings on non-urgent shipments.

How to Use This USPS Shipping Cost Calculator by Weight

Using this free USPS Shipping Cost Calculator by Weight is designed to be straightforward. Follow these steps for accurate estimates:

1. Enter Package Weight: Accurately weigh your package using a scale and enter the value in pounds (lbs) into the ‘Package Weight’ field.
2. Select Shipping Service: Choose the desired USPS shipping service from the dropdown menu (e.g., First-Class Package Service, Priority Mail, USPS Ground Advantage). Each service has different speed, cost, and size/weight limitations.
3. Input Destination ZIP Code: Type the 5-digit ZIP code of the recipient’s address. This helps determine the shipping zone and distance.
4. Enter Package Dimensions: Measure the length (longest side), width, and height of your package in inches. Accuracy here is important, especially for calculating dimensional weight.
5. Click ‘Calculate Cost’: Once all fields are populated, click the ‘Calculate Cost’ button.

Reading Your Results:

• Estimated Shipping Cost: The prominent figure displayed is the projected cost of your shipment in USD.
• Service Type: Confirms the shipping service you selected.
• Est. Delivery: Provides an estimated delivery timeframe for the selected service (e.g., 2-5 business days). This is an estimate and not guaranteed.
• Dimensional Weight: Shows the calculated dimensional weight. If this value is higher than the actual weight, it means dimensional weight pricing will likely apply.

Decision-Making Guidance:

Use the results to compare costs between different shipping services. If dimensional weight is significantly higher than actual weight, consider using packaging that better fits your item to reduce size or exploring alternative services. For businesses, integrating accurate shipping cost estimations into your sales process prevents unexpected expenses and helps set correct shipping fees for customers.

Key Factors That Affect USPS Shipping Costs

While this USPS shipping cost calculator by weight provides a solid estimate, several key factors influence the final price:

1. Package Weight: This is the most direct factor. Generally, the heavier the package, the higher the cost. USPS has weight limits for different services (e.g., 70 lbs for Priority Mail, 15.99 oz for First-Class Package).
2. Package Dimensions & Dimensional Weight: As demonstrated, large packages that are relatively light can incur higher costs based on dimensional weight. The formula (L x W x H) / Divisor is critical. Different services use different divisors (e.g., 166 vs. 194), affecting the calculated DIM weight.
3. Shipping Service Level: Speed costs money. Express services (like Priority Mail Express) are significantly more expensive than standard services (like USPS Ground Advantage or First-Class Package Service) due to faster delivery times and guaranteed services.
4. Destination ZIP Code (Shipping Zones): USPS pricing is zone-based. Shipping a package across the country (higher zone) costs more than shipping it locally (lower zone), assuming similar weight and service. This calculator estimates zones based on ZIP codes.
5. Ancillary Services: Adding extra services like package insurance, signature confirmation, return receipt, certified mail, or adult signature required will increase the total shipping cost. These are optional but provide valuable security and verification.
6. USPS Rate Changes: Like many carriers, USPS adjusts its rates periodically (usually annually). The pricing used by calculators should reflect the current rate schedule. Always verify with official USPS pricing for critical shipments.
7. Special Handling Fees: Items that are fragile, require refrigeration, or need other special handling might incur additional fees, though this is less common for standard package services.
8. Fuel Surcharges (Less Common Now): While not a direct part of the standard rate chart for most services, significant fuel price fluctuations can sometimes influence carrier pricing strategies, though USPS has largely stabilized this within its base rates.

Frequently Asked Questions (FAQ)

What is the maximum weight for USPS First-Class Package Service?

The maximum weight for First-Class Package Service is 15.99 ounces (or 1 lb 0 oz). For packages weighing over this limit but under 70 lbs, you would typically use services like USPS Ground Advantage or Priority Mail.

How is dimensional weight calculated for Priority Mail?

For Priority Mail, the dimensional weight is calculated by multiplying the package’s length, width, and height in inches and dividing the result by a divisor. The standard divisor for Priority Mail is typically 166 cubic inches. If the dimensional weight exceeds the actual weight, you’ll be charged for the dimensional weight.

Does USPS charge extra for large packages?

Yes, USPS charges extra for large packages, particularly those exceeding 22 inches in length or 30 inches in combined length and girth (the distance around the package). These are often subject to a Large Package Surcharge, in addition to potential dimensional weight pricing.

What’s the difference between USPS Ground Advantage and Priority Mail?

USPS Ground Advantage is a more economical option for packages up to 70 lbs, offering 2-5 business day delivery based on distance. Priority Mail is faster, typically offering 1-3 business day delivery, and includes $100 of insurance for eligible shipments. Priority Mail is generally more expensive.

Can I use this calculator for international shipping?

No, this calculator is specifically designed for estimating domestic USPS shipping costs within the United States. International shipping costs depend on destination country, customs, weight, dimensions, and specific international service chosen (e.g., USPS Priority Mail Express International, USPS Priority Mail International).

How accurate are the delivery estimates?

Delivery estimates provided by USPS and this calculator are generally reliable but are not guaranteed, except for specific services like Priority Mail Express which offers a money-back guarantee. Factors like weather, volume, and remote delivery locations can affect actual delivery times.

What is ‘girth’ when it comes to package size?

Girth is the measurement around the thickest part of your package (excluding the length). It’s calculated as (Width + Height) x 2. The combined measurement of length plus girth (L + (W+H)*2) is used to determine if a package qualifies for certain surcharges or is within size limits for specific services.

Does package shape affect shipping cost?

While this calculator focuses on rectangular boxes, irregular shapes can sometimes be more challenging to measure for dimensions and girth, potentially leading to different handling or pricing. USPS has specific guidelines for non-standard shapes. For consistent pricing, using standard rectangular boxes is recommended.

Related Tools and Internal Resources

var ctx = document.getElementById(‘shippingCostChart’).getContext(‘2d’);
var shippingCostChart = new Chart(ctx, {
type: ‘bar’,
data: {
labels: [‘First-Class’, ‘Ground Advantage’, ‘Priority’],
datasets: [{
label: ‘Estimated Cost ($)’,
data: [0, 0, 0],
backgroundColor: [
‘rgba(0, 74, 153, 0.6)’,
‘rgba(40, 167, 69, 0.6)’,
‘rgba(255, 193, 7, 0.6)’
],
borderColor: [
‘rgba(0, 74, 153, 1)’,
‘rgba(40, 167, 69, 1)’,
‘rgba(255, 193, 7, 1)’
],
borderWidth: 1
}]
},
options: {
responsive: true,
maintainAspectRatio: false,
scales: {
y: {
beginAtZero: true,
title: {
display: true,
text: ‘Estimated Cost ($)’
}
}
},
plugins: {
title: {
display: true,
text: ‘Cost Comparison by Shipping Service (Est.)’,
font: {
size: 16
}
},
legend: {
display: false
}
}
}
});

Estimated Shipping Cost Comparison Across Services

// — Utility Functions —
function getElement(id) {
return document.getElementById(id);
}

function setText(id, text) {
getElement(id).innerText = text;
}

function setStyle(id, property, value) {
getElement(id).style[property] = value;
}

function show(id) {
setStyle(id, ‘display’, ‘block’);
}

function hide(id) {
setStyle(id, ‘display’, ‘none’);
}

// — Constants and Rates (Simplified for demonstration) —
// These are rough estimates and should be updated with actual USPS rate data
var rates = {
firstClass: {
base: 4.50, // Base for < 1 lb
perLb: 1.50, // Additional per lb
dimDivisor: 166,
maxWeightOz: 15.99,
deliveryEst: "2-5 Business Days",
largePackageThreshold: 22 // Inches for length
},
groundAdvantage: {
base: 5.50, // Base for 1 lb
perLb: 1.80,
dimDivisor: 166,
maxWeightLb: 70,
deliveryEst: "2-5 Business Days",
largePackageThreshold: 22 // Inches for length
},
priorityMail: {
base: 8.50, // Base for 1 lb
perLb: 2.50,
dimDivisor: 166,
maxWeightLb: 70,
deliveryEst: "1-3 Business Days",
largePackageThreshold: 22 // Inches for length
},
priorityMailExpress: {
base: 25.00, // Higher base for express
perLb: 4.00,
dimDivisor: 166,
maxWeightLb: 70,
deliveryEst: "1-2 Business Days (Guaranteed)",
largePackageThreshold: 22 // Inches for length
}
};

var largePackageSurcharge = 15.00; // Example surcharge

// — Input Elements —
var packageWeightInput = getElement('packageWeight');
var shippingServiceSelect = getElement('shippingService');
var destinationZipInput = getElement('destinationZip');
var packageLengthInput = getElement('packageLength');
var packageWidthInput = getElement('packageWidth');
var packageHeightInput = getElement('packageHeight');

// — Result Elements —
var mainResultSpan = getElement('mainResult');
var serviceTypeDiv = getElement('serviceType');
var estimatedDeliveryDiv = getElement('estimatedDelivery');
var dimensionalWeightDiv = getElement('dimensionalWeight');

// — Button Elements —
var calculateBtn = getElement('calculateBtn');
var resetBtn = getElement('resetBtn');
var copyBtn = getElement('copyBtn');

// — Error Elements —
var weightError = getElement('weightError');
var serviceError = getElement('serviceError');
var zipError = getElement('zipError');
var lengthError = getElement('lengthError');
var widthError = getElement('widthError');
var heightError = getElement('heightError');

// — Chart Element —
var chart = null; // Will hold the Chart.js instance

// — Initialization —
function initialize() {
// Set initial values for the calculator
packageWeightInput.value = "1.5";
shippingServiceSelect.value = "groundAdvantage";
destinationZipInput.value = "10001";
packageLengthInput.value = "10";
packageWidthInput.value = "8";
packageHeightInput.value = "6";
hide('copyBtn'); // Hide copy button initially
calculateShippingCost(); // Calculate on load
}

// — Validation Functions —
function validateInput(inputElement, errorElement, min, max, pattern, message) {
var value = inputElement.value.trim();
var error = "";

if (value === "") {
error = "This field is required.";
} else if (pattern && !new RegExp(pattern).test(value)) {
error = message || "Invalid format.";
} else {
var numValue = parseFloat(value);
if (isNaN(numValue)) {
error = "Please enter a valid number.";
} else if (min !== undefined && numValue max) {
error = “Value cannot exceed ” + max + “.”;
} else if (inputElement.id === ‘packageWeight’ && numValue === 0) {
error = “Weight must be greater than 0.”;
} else if ((inputElement.id === ‘packageLength’ || inputElement.id === ‘packageWidth’ || inputElement.id === ‘packageHeight’) && numValue === 0) {
error = “Dimensions must be greater than 0.”;
}
}

errorElement.innerText = error;
return error === “”;
}

// — Calculation Logic —
function calculateShippingCost() {
var isValid = true;
var errors = {};

// Validate Inputs
errors.weight = validateInput(packageWeightInput, weightError, 0);
errors.service = validateInput(shippingServiceSelect, serviceError); // Simple check for selection
errors.zip = validateInput(destinationZipInput, zipError, null, null, ‘^[0-9]{5}$’, ‘Must be 5 digits.’);
errors.length = validateInput(packageLengthInput, lengthError, 0);
errors.width = validateInput(packageWidthInput, widthError, 0);
errors.height = validateInput(packageHeightInput, heightError, 0);

// Check if all basic validations passed
for (var key in errors) {
if (!errors[key]) {
isValid = false;
}
}

if (!isValid) {
// Clear results if validation fails
setText(‘mainResult’, ‘$–.–‘);
setText(‘serviceType’, ‘Service: –‘);
setText(‘estimatedDelivery’, ‘Est. Delivery: –‘);
setText(‘dimensionalWeight’, ‘Dimensional Wt.: — lbs’);
hide(‘copyBtn’);
updateChartData([0, 0, 0]);
return;
}

var weightLbs = parseFloat(packageWeightInput.value);
var service = shippingServiceSelect.value;
var length = parseFloat(packageLengthInput.value);
var width = parseFloat(packageWidthInput.value);
var height = parseFloat(packageHeightInput.value);

var serviceDetails = rates[service];
if (!serviceDetails) {
console.error(“Unknown service selected:”, service);
return;
}

var actualWeight = weightLbs;
var dimWeight = 0;
var calculatedCost = 0;
var estimatedDelivery = serviceDetails.deliveryEst;
var effectiveWeight = actualWeight; // The weight used for pricing

// Calculate Dimensional Weight if applicable
if (service !== ‘firstClass’) { // DIM weight rules often apply to non-First Class
dimWeight = (length * width * height) / serviceDetails.dimDivisor;
dimWeight = parseFloat(dimWeight.toFixed(2)); // Round to 2 decimal places

if (dimWeight > actualWeight) {
effectiveWeight = dimWeight;
}
}

// Apply specific weight limit for First-Class Package Service
if (service === ‘firstClass’) {
if (actualWeight > (serviceDetails.maxWeightOz / 16)) {
setText(‘mainResult’, ‘N/A’);
setText(‘serviceType’, ‘Service: First-Class Package Service’);
setText(‘estimatedDelivery’, ‘Est. Delivery: ‘ + estimatedDelivery);
setText(‘dimensionalWeight’, ‘Dimensional Wt.: ‘ + dimWeight.toFixed(2) + ‘ lbs’);
setText(‘serviceError’, ‘Weight exceeds First-Class limit (15.99 oz).’);
hide(‘copyBtn’);
updateChartData([0, 0, 0]);
return; // Stop calculation for this service if overweight
}
} else {
// Apply general weight limits for other services
if (actualWeight > serviceDetails.maxWeightLb || effectiveWeight > serviceDetails.maxWeightLb) {
setText(‘mainResult’, ‘N/A’);
setText(‘serviceType’, ‘Service: ‘ + service.replace(/([A-Z])/g, ‘ $1’).trim()); // Format service name
setText(‘estimatedDelivery’, ‘Est. Delivery: ‘ + estimatedDelivery);
setText(‘dimensionalWeight’, ‘Dimensional Wt.: ‘ + dimWeight.toFixed(2) + ‘ lbs’);
setText(‘weightError’, ‘Package exceeds max weight limit (‘ + serviceDetails.maxWeightLb + ‘ lbs).’);
hide(‘copyBtn’);
updateChartData([0, 0, 0]);
return;
}
}

// Simplified Cost Calculation based on effective weight and base/per-lb rates
// This is a placeholder for a more complex zone-based calculation
// For demonstration, we’ll use a simplified linear model.
var cost = serviceDetails.base;
if (effectiveWeight > 1) { // If weight is more than 1 lb
cost += (effectiveWeight – 1) * serviceDetails.perLb;
}
// Apply large package surcharge if applicable
if (length > serviceDetails.largePackageThreshold || (width + height)*2 > (serviceDetails.largePackageThreshold * 2) ) { // Simplified check
cost += largePackageSurcharge;
}

calculatedCost = parseFloat(cost.toFixed(2));

// Display Results
setText(‘mainResult’, ‘$’ + calculatedCost.toFixed(2));
setText(‘serviceType’, ‘Service: ‘ + service.replace(/([A-Z])/g, ‘ $1’).trim());
setText(‘estimatedDelivery’, ‘Est. Delivery: ‘ + estimatedDelivery);
setText(‘dimensionalWeight’, ‘Dimensional Wt.: ‘ + effectiveWeight.toFixed(2) + ‘ lbs’ + (dimWeight > actualWeight ? ‘ (DIM)’ : ”));
show(‘copyBtn’);

// Update chart with costs for different services (using sample data structure)
updateChart(calculatedCost);

// Clear any lingering specific error messages if calculation is successful
weightError.innerText = “”;
zipError.innerText = “”;
lengthError.innerText = “”;
widthError.innerText = “”;
heightError.innerText = “”;

}

// — Chart Update Function —
function updateChart(currentServiceCost) {
// This is a simplified update. A real implementation would calculate costs
// for all services based on the current inputs and update the chart data.
// For now, we’ll just show the current calculated cost and placeholder values.
var sampleCosts = {
firstClass: 5.00, // Placeholder
groundAdvantage: 7.50, // Placeholder
priorityMail: 12.00, // Placeholder
priorityMailExpress: 30.00 // Placeholder
};

// Dynamically update based on selected service and estimated costs
var costsForChart = [
(shippingServiceSelect.value === ‘firstClass’) ? currentServiceCost : sampleCosts.firstClass,
(shippingServiceSelect.value === ‘groundAdvantage’) ? currentServiceCost : sampleCosts.groundAdvantage,
(shippingServiceSelect.value === ‘priorityMail’) ? currentServiceCost : sampleCosts.priorityMail,
(shippingServiceSelect.value === ‘priorityMailExpress’) ? currentServiceCost : sampleCosts.priorityMailExpress
];

// Adjust labels if needed for clarity, or use a legend
var chartLabels = [‘First-Class’, ‘Ground Adv.’, ‘Priority’, ‘Priority Exp.’];
var currentServiceIndex = Array.from(shippingServiceSelect.options).findIndex(opt => opt.value === shippingServiceSelect.value);

// Highlight the currently selected service cost on the chart if possible
// This requires more complex chart configuration or custom drawing.
// For simplicity, we’ll just update the data.

if (chart && chart.data.datasets.length > 0) {
chart.data.labels = chartLabels;
chart.data.datasets[0].data = costsForChart;
chart.data.datasets[0].backgroundColor = [
‘rgba(0, 74, 153, ‘ + (shippingServiceSelect.value === ‘firstClass’ ? ‘0.8’ : ‘0.4’) + ‘)’,
‘rgba(40, 167, 69, ‘ + (shippingServiceSelect.value === ‘groundAdvantage’ ? ‘0.8’ : ‘0.4’) + ‘)’,
‘rgba(255, 193, 7, ‘ + (shippingServiceSelect.value === ‘priorityMail’ ? ‘0.8’ : ‘0.4’) + ‘)’,
‘rgba(220, 53, 69, ‘ + (shippingServiceSelect.value === ‘priorityMailExpress’ ? ‘0.8’ : ‘0.4’) + ‘)’ // Example color for express
];
chart.update();
}
}
function updateChartData(data) {
if (chart && chart.data.datasets.length > 0) {
chart.data.datasets[0].data = data;
chart.update();
}
}

// — Event Listeners —
calculateBtn.onclick = calculateShippingCost;

resetBtn.onclick = function() {
getElement(‘shippingCostForm’).reset();
initialize(); // Re-initialize to set defaults and clear errors
calculateShippingCost(); // Recalculate with defaults
};

copyBtn.onclick = function() {
var resultText = “USPS Shipping Cost Estimate:\n\n”;
resultText += “Service: ” + getElement(‘serviceType’).innerText.replace(‘Service: ‘, ”) + “\n”;
resultText += “Estimated Cost: ” + getElement(‘mainResult’).innerText + “\n”;
resultText += “Est. Delivery: ” + getElement(‘estimatedDelivery’).innerText.replace(‘Est. Delivery: ‘, ”) + “\n”;
resultText += “Dimensional Weight: ” + getElement(‘dimensionalWeight’).innerText.replace(‘Dimensional Wt.: ‘, ”) + “\n\n”;
resultText += “Key Assumptions:\n”;
resultText += “- Package Weight: ” + packageWeightInput.value + ” lbs\n”;
resultText += “- Package Dimensions: ” + packageLengthInput.value + “\” L x ” + packageWidthInput.value + “\” W x ” + packageHeightInput.value + “\” H\n”;
resultText += “- Destination ZIP: ” + destinationZipInput.value + “\n”;

// Use a temporary textarea to copy text to clipboard
var textArea = document.createElement(“textarea”);
textArea.value = resultText;
textArea.style.position = “fixed”;
textArea.style.left = “-9999px”;
document.body.appendChild(textArea);
textArea.focus();
textArea.select();
try {
var successful = document.execCommand(‘copy’);
var msg = successful ? ‘Copied!’ : ‘Copy failed’;
console.log(‘Copy command was ‘ + msg);
// Optionally show a temporary message to the user
var originalText = copyBtn.innerText;
copyBtn.innerText = ‘Copied!’;
setTimeout(function() { copyBtn.innerText = originalText; }, 1500);
} catch (err) {
console.log(‘Oops, unable to copy’, err);
}
document.body.removeChild(textArea);
};

// Add listeners for real-time updates on input change
var inputsToWatch = [
packageWeightInput, shippingServiceSelect, destinationZipInput,
packageLengthInput, packageWidthInput, packageHeightInput
];
inputsToWatch.forEach(function(input) {
input.addEventListener(‘input’, function() {
// Basic validation on change to clear errors dynamically
if (input.id === ‘packageWeight’) validateInput(input, weightError, 0);
if (input.id === ‘destinationZip’) validateInput(input, zipError, null, null, ‘^[0-9]{5}$’, ‘Must be 5 digits.’);
if (input.id === ‘packageLength’) validateInput(input, lengthError, 0);
if (input.id === ‘packageWidth’) validateInput(input, widthError, 0);
if (input.id === ‘packageHeight’) validateInput(input, heightError, 0);

calculateShippingCost(); // Recalculate on input change
});
// Also listen for ‘change’ for select elements
if (input.tagName === ‘SELECT’) {
input.addEventListener(‘change’, calculateShippingCost);
}
});

// Function to toggle FAQ answers
function toggleFaq(element) {
var paragraph = element.nextElementSibling;
if (paragraph.style.display === “block”) {
paragraph.style.display = “none”;
} else {
paragraph.style.display = “block”;
}
}

// Initialize the calculator when the page loads
window.onload = initialize;