function calculateShippingRates() {
// 1. Get Input Values
var weight = parseFloat(document.getElementById('packageWeight').value);
var length = parseFloat(document.getElementById('dimLength').value);
var width = parseFloat(document.getElementById('dimWidth').value);
var height = parseFloat(document.getElementById('dimHeight').value);
var zone = parseInt(document.getElementById('shippingZone').value);
var service = document.getElementById('serviceLevel').value;
// 2. Validate Inputs
if (isNaN(weight) || weight 0 && width > 0 && height > 0) {
dimWeight = (length * width * height) / 139;
}
// Billable weight is the greater of Actual Weight vs Dim Weight
var billableWeight = Math.max(weight, dimWeight);
// Round up to nearest pound for pricing
billableWeight = Math.ceil(billableWeight);
// 4. Logic: Base Rate Table Simulation
// This is a simplified mathematical model to estimate rates based on Zone and Weight.
// Real rates require API, but this simulates the curve.
// Base starting price for Zone 1, 1lb
var basePrice = 8.50;
// Cost per additional pound (approximate average)
var costPerLb = 0.75;
// Cost multiplier per Zone distance
var zoneMultiplier = 1 + (zone * 0.12); // Increases price by 12% per zone roughly
// Calculate Raw Ground Rate
var estimatedRetail = (basePrice + (billableWeight * costPerLb)) * zoneMultiplier;
// 5. Logic: Service Level Multipliers
var serviceMultiplier = 1.0;
var discountFactor = 0.0; // Shippo discount varies by service
if (service === 'ground') {
serviceMultiplier = 1.0;
discountFactor = 0.40; // ~40% off ground (e.g. UPS Ground via Shippo)
} else if (service === 'priority') {
serviceMultiplier = 1.6; // Priority is more expensive
discountFactor = 0.55; // ~55% off Priority (e.g. USPS Priority Mail)
} else if (service === 'express') {
serviceMultiplier = 3.5; // Overnight is very expensive
discountFactor = 0.65; // High discounts on overnight (e.g. UPS Next Day Air)
}
// Adjust Retail Price based on Service
var finalRetailPrice = estimatedRetail * serviceMultiplier;
// 6. Logic: Calculate Shippo Discounted Price
// Shippo offers commercial pricing (Cubic, Commercial Plus, etc.)
var shippoPrice = finalRetailPrice * (1 – discountFactor);
// 7. Update UI
document.getElementById('retailRateDisplay').innerHTML = '$' + finalRetailPrice.toFixed(2);
document.getElementById('shippoRateDisplay').innerHTML = '$' + shippoPrice.toFixed(2);
var savingsAmount = finalRetailPrice – shippoPrice;
var savingsPercent = (savingsAmount / finalRetailPrice) * 100;
document.getElementById('savingsDisplay').innerHTML = 'Total Savings: $' + savingsAmount.toFixed(2) + ' (' + Math.round(savingsPercent) + '%)';
var weightMsg = "Billable Weight used: " + billableWeight + " lbs";
if (dimWeight > weight) {
weightMsg += " (Based on Dimensional Weight of " + Math.ceil(dimWeight) + " lbs)";
} else {
weightMsg += " (Based on Actual Weight)";
}
document.getElementById('dimWeightDisplay').innerHTML = weightMsg;
document.getElementById('shippo-results').style.display = 'block';
}
Understanding Shipping Rates with Shippo
Shipping costs are one of the largest expenses for e-commerce businesses. Platforms like Shippo connect merchants directly with carriers (such as USPS, UPS, FedEx, and DHL) to provide discounted shipping labels that are significantly cheaper than standard retail rates you would pay at the post office counter.
This Shippo Shipping Rates Estimator helps you calculate potential shipping costs based on the variables that matter most: weight, dimensions, distance (zones), and service level.
Key Factors That Influence Your Shipping Rate
When calculating shipping costs, carriers do not look at weight alone. To get an accurate estimate, you must understand the following four components:
Actual Weight: The physical weight of the package as measured on a scale.
Dimensional (DIM) Weight: A calculation based on the package size (Length × Width × Height / Divisor). Carriers charge based on whichever is greater: actual weight or DIM weight. Light but bulky packages cost more.
Shipping Zones: In the US, distance is measured in "Zones" ranging from Zone 1 (local) to Zone 8 (cross-country). The higher the zone, the higher the rate.
Service Level: Faster delivery times (Overnight/Express) incur exponential cost increases compared to Ground or Economy services.
How Shippo Saves You Money
Shippo aggregates volume from thousands of merchants to negotiate "Commercial Plus" and "Commercial Base" pricing. This allows small businesses to access rates typically reserved for enterprise giants.
Service Type
Typical Retail Cost
Shippo/Commercial Cost
Potential Savings
USPS Priority Mail
High
Low
Up to 40%
UPS Ground
Medium
Low
Up to 70%
International
Very High
Medium
Up to 65%
What is Dimensional Weight?
If you enter dimensions into the calculator above, you might notice the "Billable Weight" increases. This is Dimensional Weight in action. For example, a large pillow might only weigh 2 lbs, but if it is in a 20″x20″x20″ box, carriers may charge you as if it weighed 58 lbs. Always use the smallest box possible to reduce your Shippo rates.
Frequently Asked Questions
Is Shippo free to use?
Shippo has a "Starter" plan that has no monthly subscription fee; you only pay the cost of the postage plus a small per-label fee. They also offer subscription plans for high-volume shippers.
How accurate is this calculator?
This tool provides an estimate based on standard industry pricing models and average discounts available through multi-carrier software. Exact rates depend on your specific origin zip code, carrier fuel surcharges, and current seasonal demand.