USPS Package Girth and Size Calculator
Use this calculator to determine your package's girth and combined length plus girth, which are critical dimensions USPS uses to classify packages and apply shipping rates. Understanding these measurements can help you avoid unexpected surcharges for large or oversized items.
How to Measure Your Package for USPS:
- Longest Side: Identify the longest dimension of your package.
- Girth: Measure the distance around the thickest part of the package perpendicular to its length. An easy way to do this is to measure the width and height, then calculate:
(2 x Width) + (2 x Height). - Combined Length + Girth: Add the longest side measurement to the calculated girth.
All measurements should be in inches.
Understanding USPS Package Size Limits and Surcharges:
USPS uses the "Combined Length + Girth" measurement to determine if a package is standard, subject to a large package surcharge, or considered oversized (balloon rate). These classifications directly impact your shipping costs, especially for services like Priority Mail and Ground Advantage.
- Standard Package: Typically, packages with a Combined Length + Girth of 108 inches or less.
- Large Package Surcharge: Applied to packages with a Combined Length + Girth greater than 108 inches but up to 130 inches. This incurs an additional fee.
- Oversized / Balloon Rate: Applied to packages with a Combined Length + Girth greater than 130 inches but up to 165 inches. These packages are subject to significantly higher rates, often based on a minimum weight (e.g., 20 lbs for Ground Advantage, 20 lbs for Priority Mail if over 1 cubic foot).
- Unmailable: Packages exceeding 165 inches in Combined Length + Girth are generally not accepted by USPS for most services.
Always ensure your measurements are accurate to avoid unexpected shipping costs or package rejections. This calculator provides an estimate based on common USPS domestic service rules.
function calculateUSPSGirth() { var longestSideInput = document.getElementById("longestSide").value; var widthInput = document.getElementById("width").value; var heightInput = document.getElementById("height").value; var resultDiv = document.getElementById("result"); var longestSide = parseFloat(longestSideInput); var width = parseFloat(widthInput); var height = parseFloat(heightInput); if (isNaN(longestSide) || isNaN(width) || isNaN(height) || longestSide <= 0 || width <= 0 || height 108 && combinedLG 130 && combinedLG 165) { packageClassification = "Unmailable"; classificationDetails = " (Exceeds maximum size for most USPS services)"; } resultDiv.innerHTML = "Calculated Girth: " + girth.toFixed(2) + " inches" + "Combined Length + Girth: " + combinedLG.toFixed(2) + " inches" + "USPS Package Classification: " + packageClassification + "" + classificationDetails + ""; } .usps-girth-calculator-container { font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif; background-color: #f9f9f9; padding: 25px; border-radius: 8px; box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1); max-width: 700px; margin: 20px auto; color: #333; } .usps-girth-calculator-container h2, .usps-girth-calculator-container h3 { color: #005792; margin-bottom: 15px; border-bottom: 1px solid #eee; padding-bottom: 10px; } .usps-girth-calculator-container p { line-height: 1.6; margin-bottom: 10px; } .usps-girth-calculator-container ol, .usps-girth-calculator-container ul { margin-left: 20px; margin-bottom: 15px; } .usps-girth-calculator-container li { margin-bottom: 5px; } .calculator-form label { display: inline-block; margin-bottom: 8px; font-weight: bold; width: 180px; /* Align labels */ } .calculator-form input[type="number"] { width: 150px; padding: 10px; margin-bottom: 10px; border: 1px solid #ccc; border-radius: 4px; box-sizing: border-box; } .calculator-form button { background-color: #007bff; color: white; padding: 12px 20px; border: none; border-radius: 5px; cursor: pointer; font-size: 16px; transition: background-color 0.3s ease; margin-top: 10px; } .calculator-form button:hover { background-color: #0056b3; } #result { margin-top: 25px; padding: 15px; border: 1px solid #ddd; border-radius: 5px; background-color: #eaf6ff; color: #005792; } #result p { margin: 5px 0; }