Standard Letter (Stamped)
Metered Letter
Large Envelope (Flat)
Postcard
Max weight for standard letters is 3.5 oz.
Mail Type:–
Billable Weight:–
Base Rate (1st oz):–
Additional Ounces Cost:–
Total Postage: $0.00
function updateWeightNote() {
var type = document.getElementById('mailType').value;
var note = document.getElementById('weightNote');
if (type === 'letter' || type === 'metered') {
note.innerText = "Max weight for letters is 3.5 oz. Weights above 3.5 oz are charged as Large Envelopes.";
} else if (type === 'flat') {
note.innerText = "Max weight for Large Envelopes is 13 oz.";
} else if (type === 'postcard') {
note.innerText = "Standard postcards must be rectangular. Max size 6\" x 4.25\".";
}
}
function calculatePostage() {
// July 2024 Rates
var RATE_LETTER_BASE = 0.73;
var RATE_METERED_BASE = 0.69;
var RATE_FLAT_BASE = 1.50;
var RATE_POSTCARD = 0.56;
var RATE_ADDITIONAL_OZ = 0.24;
var type = document.getElementById('mailType').value;
var weightRaw = parseFloat(document.getElementById('mailWeight').value);
var errorDiv = document.getElementById('errorDisplay');
var resultDiv = document.getElementById('resultDisplay');
var extraOzRow = document.getElementById('extraOzRow');
// Reset display
errorDiv.style.display = 'none';
resultDiv.style.display = 'none';
errorDiv.innerHTML = ";
// Validation
if (isNaN(weightRaw) || weightRaw 1) {
// Technically a heavy postcard becomes a letter, but for simplicity we warn
errorDiv.innerHTML = "Note: Heavy or oversized postcards may be charged as Letters ($0.73).";
errorDiv.style.display = 'block';
}
} else if (type === 'letter') {
displayType = "Standard Letter (Stamped)";
if (weightRaw > 3.5) {
errorDiv.innerHTML = "Weight exceeds 3.5 oz limit for Standard Letters. Calculated as Large Envelope.";
errorDiv.style.display = 'block';
// Switch logic to Flat automatically
type = 'flat';
// Fall through to flat logic below…
} else {
baseCost = RATE_LETTER_BASE;
var additionalOunces = (weightRounded > 1) ? (weightRounded – 1) : 0;
extraCost = additionalOunces * RATE_ADDITIONAL_OZ;
totalCost = baseCost + extraCost;
extraOzRow.style.display = 'flex';
}
} else if (type === 'metered') {
displayType = "Metered Letter";
if (weightRaw > 3.5) {
errorDiv.innerHTML = "Weight exceeds 3.5 oz limit for Metered Letters. Calculated as Large Envelope.";
errorDiv.style.display = 'block';
type = 'flat'; // Switch to flat
} else {
baseCost = RATE_METERED_BASE;
var additionalOunces = (weightRounded > 1) ? (weightRounded – 1) : 0;
extraCost = additionalOunces * RATE_ADDITIONAL_OZ;
totalCost = baseCost + extraCost;
extraOzRow.style.display = 'flex';
}
}
// Handle Flat logic (either selected directly OR converted from heavy letter)
if (type === 'flat') {
displayType = "Large Envelope (Flat)";
if (weightRaw > 13) {
errorDiv.innerHTML = "Weight exceeds 13 oz limit for First-Class Mail Large Envelopes. You must use USPS Ground Advantage.";
errorDiv.style.display = 'block';
return; // Stop calculation
}
baseCost = RATE_FLAT_BASE;
var additionalOunces = (weightRounded > 1) ? (weightRounded – 1) : 0;
extraCost = additionalOunces * RATE_ADDITIONAL_OZ;
totalCost = baseCost + extraCost;
extraOzRow.style.display = 'flex';
}
// Update DOM
document.getElementById('resType').innerText = displayType;
document.getElementById('resWeight').innerText = (type === 'postcard') ? "Up to 4.25\" x 6\"" : weightRounded + " oz";
document.getElementById('resBase').innerText = "$" + baseCost.toFixed(2);
document.getElementById('resExtra').innerText = "$" + extraCost.toFixed(2);
document.getElementById('resTotal').innerText = "$" + totalCost.toFixed(2);
resultDiv.style.display = 'block';
}
Understanding USPS First Class Mail Rates in 2024
Postage rates are a critical component for small businesses and individuals sending mail within the United States. As of July 14, 2024, the United States Postal Service (USPS) implemented new price adjustments for First-Class Mail products. This USPS First Class Postage Rate 2024 Calculator helps you determine the exact cost of sending letters, large envelopes (flats), and postcards based on the current pricing structure.
Current 2024 Postage Rates (Effective July 2024)
The cost of a "Forever" stamp increased from 68 cents to 73 cents in July 2024. Below is a breakdown of the standard retail rates used by this calculator:
Mail Type
Base Price (1 oz)
Each Additional Ounce
Standard Letter (Stamped)
$0.73
$0.24
Metered Letter
$0.69
$0.24
Large Envelope (Flat)
$1.50
$0.24
Postcard
$0.56 (Flat Rate)
N/A
Weight Limits and Rules
When calculating your postage, it is important to understand the physical limitations of each mail class:
Letters: Standard letters must weigh 3.5 ounces or less. If a letter weighs more than 3.5 ounces, it is automatically classified as a Large Envelope (Flat), which has a higher starting price.
Large Envelopes (Flats): These must weigh 13 ounces or less. Any item weighing more than 13 ounces cannot be sent via First-Class Mail and must be shipped via USPS Ground Advantage or Priority Mail.
Rounding: The USPS rounds up weights to the next whole ounce. For example, a letter weighing 1.1 ounces is charged at the 2-ounce rate.
Difference Between Standard and Metered Mail
If you use a postage meter in your office or business, you receive a discount on the first ounce of a letter. While a retail stamp costs $0.73, a metered letter costs only $0.69 for the first ounce. The cost for additional ounces ($0.24) remains the same for both methods.
What happened to First Class Package Service?
In mid-2023, the USPS consolidated First Class Package Service into a new service called USPS Ground Advantage. Therefore, if you are shipping a parcel (a thick envelope or box), you should refer to Ground Advantage rates, which are calculated based on weight (up to 70 lbs) and distance (Zone), rather than the flat ounce-based increments of First-Class Mail letters.