Marketing Mail (Commercial)
Marketing Mail (Non-Profit)
First-Class Mail Presort
Letter (Up to 3.5 oz)
Flat / Large Envelope
Postcard (First-Class Only)
Minimum required: 200 pieces
Estimated Postage Costs
Estimated Bulk Rate (Per Piece):$0.00
Retail Rate (Comparison):$0.00
Total Retail Cost:$0.00
Total Bulk Cost:$0.00
Estimated Savings:$0.00
function updateRequirements() {
var mailClass = document.getElementById("mailClass").value;
var note = document.getElementById("minQtyNote");
var shape = document.getElementById("mailShape");
// Disable postcard for marketing mail as there is no specific postcard rate (treated as letter)
// Re-enable for first class
var postcardOpt = shape.querySelector('option[value="postcard"]');
if (mailClass === "first_class_presort") {
note.innerText = "Minimum required: 500 pieces";
postcardOpt.disabled = false;
} else {
note.innerText = "Minimum required: 200 pieces (or 50 lbs)";
if(shape.value === "postcard") {
shape.value = "letter";
}
postcardOpt.disabled = true;
}
}
function calculatePostage() {
// Inputs
var mailClass = document.getElementById("mailClass").value;
var mailShape = document.getElementById("mailShape").value;
var quantity = parseFloat(document.getElementById("mailQuantity").value);
var weight = parseFloat(document.getElementById("pieceWeight").value);
var errorDisplay = document.getElementById("errorDisplay");
var resultsArea = document.getElementById("resultsArea");
// Reset display
errorDisplay.style.display = "none";
resultsArea.style.display = "none";
errorDisplay.innerText = "";
// Validation
if (isNaN(quantity) || quantity <= 0) {
errorDisplay.innerText = "Please enter a valid quantity.";
errorDisplay.style.display = "block";
return;
}
if (isNaN(weight) || weight <= 0) {
errorDisplay.innerText = "Please enter a valid weight per piece.";
errorDisplay.style.display = "block";
return;
}
// Minimum Quantity Logic
var minQty = (mailClass === "first_class_presort") ? 500 : 200;
if (quantity 3.5) {
errorDisplay.innerText = "Letters cannot weigh more than 3.5 oz. Please switch Shape to 'Flat'.";
errorDisplay.style.display = "block";
return;
}
if (mailShape === "postcard" && weight > 4.0) { // technically cards have smaller limits but strict max is small
// First class postcard max is 6×9 and specific weight, usually treated as letter if heavy
// Keeping simple logic
}
// Rate Logic (Estimates based on Average Automation/Mixed AADC Rates 2024/2025)
var bulkRatePerPiece = 0;
var retailRatePerPiece = 0;
// Retail Rates (Approx)
if (mailShape === "letter") {
// Retail Stamp
retailRatePerPiece = 0.73; // Base 1 oz
if (weight > 1) {
retailRatePerPiece += Math.ceil(weight – 1) * 0.24; // Additional oz
}
} else if (mailShape === "flat") {
// Retail Flat
retailRatePerPiece = 1.50; // Base 1 oz
if (weight > 1) {
retailRatePerPiece += Math.ceil(weight – 1) * 0.24;
}
} else if (mailShape === "postcard") {
retailRatePerPiece = 0.56;
}
// Bulk Rates Logic
if (mailClass === "marketing_commercial") {
// Marketing Mail Commercial
if (mailShape === "letter") {
// Avg Auto Letter
bulkRatePerPiece = 0.38;
} else if (mailShape === "flat") {
// Flats cost more.
// Approx rate for 4oz includes pound rate.
if (weight <= 4) {
bulkRatePerPiece = 0.89; // Base flat rate estimate
} else {
// Piece + Pound rate estimate
// Piece ~0.60 + Weight(lbs) * 1.30
var weightLbs = weight / 16;
bulkRatePerPiece = 0.60 + (weightLbs * 1.30);
}
}
} else if (mailClass === "marketing_nonprofit") {
// Nonprofit
if (mailShape === "letter") {
bulkRatePerPiece = 0.22;
} else if (mailShape === "flat") {
if (weight 1 && weight 1) {
bulkRatePerPiece += Math.ceil(weight – 1) * 0.24;
}
} else if (mailShape === "postcard") {
bulkRatePerPiece = 0.40;
}
}
// Calculation
var totalBulk = bulkRatePerPiece * quantity;
var totalRetail = retailRatePerPiece * quantity;
var savings = totalRetail – totalBulk;
// Output
document.getElementById("resRatePerPiece").innerText = "$" + bulkRatePerPiece.toFixed(3);
document.getElementById("resRetailRate").innerText = "$" + retailRatePerPiece.toFixed(2);
document.getElementById("resTotalBulk").innerText = "$" + totalBulk.toLocaleString('en-US', {minimumFractionDigits: 2, maximumFractionDigits: 2});
document.getElementById("resTotalRetail").innerText = "$" + totalRetail.toLocaleString('en-US', {minimumFractionDigits: 2, maximumFractionDigits: 2});
document.getElementById("resSavings").innerText = "$" + savings.toLocaleString('en-US', {minimumFractionDigits: 2, maximumFractionDigits: 2});
resultsArea.style.display = "block";
}
// Initialize logic
updateRequirements();
Understanding USPS Bulk Mail Rates
USPS Bulk Mail (officially known as USPS Marketing Mail or Presorted First-Class Mail) allows businesses and organizations to send large quantities of mail at significantly reduced postage rates. Unlike retail stamps, bulk rates require the sender to perform some of the work typically done by the Post Office, such as sorting the mail by zip code and meeting minimum quantity requirements.
Minimum Quantity Requirements
To qualify for bulk postage rates, your mailing must meet specific volume thresholds:
USPS Marketing Mail: Requires a minimum of 200 pieces or 50 lbs of mail. This class is ideal for advertisements, newsletters, and flyers. Delivery is slower than First-Class.
Presorted First-Class Mail: Requires a minimum of 500 pieces. This class includes the same speed and forwarding services as regular stamps but at a discount.
Commercial vs. Non-Profit Rates
Commercial Rates are available to any business. Non-Profit Rates provide the deepest discounts but are exclusively available to organizations authorized by the USPS (like charities, churches, and political organizations). As shown in the calculator, Non-Profit letters can cost as little as $0.20 per piece, compared to the standard retail stamp price.
Mail Shape Matters
The physical shape of your mail dramatically impacts the price. A standard "Letter" must be rectangular and usually under 3.5 ounces (for automation rates). If your mailpiece is square, rigid, or exceeds dimensions (6-1/8″ x 11-1/2″), it is classified as a "Flat" (Large Envelope), which costs significantly more. Always verify your mailpiece design with a Mailpiece Design Analyst (MDA) before printing.
How to Calculate Savings
This calculator estimates your postage costs by comparing the Standard Retail Rate (what you would pay at the counter) against the Average Bulk Rate. The exact bulk rate depends on "density"—how many mailpieces are going to the same zip code. The more concentrated your mailing list is in specific areas (5-Digit sort), the lower your rate will be.