Freight Class Calculator

Freight class is one of the most critical factors in determining LTL (Less Than Truckload) shipping costs. The National Motor Freight Classification (NMFC) system assigns freight classes ranging from 50 to 500 based on four key factors: density, stowability, handling, and liability. Our freight class calculator focuses on density—the most common factor—to give you an instant estimate of your shipment's class.

Understanding your freight class before booking a shipment is essential for accurate budgeting. Carriers will reclassify your freight if the actual class differs from what you declared, often resulting in additional charges and billing disputes. By calculating your freight class upfront, you can quote customers accurately and avoid costly surprises.

The density-based freight class system works on a simple principle: the more space your freight takes up relative to its weight, the higher the class and the more expensive it is to ship. A pallet of lead weights has a low class (high density), while a pallet of ping pong balls has a high class (low density). This is why accurate measurements are crucial.

Freight brokers use freight class calculators dozens of times per day. Whether you're quoting a new customer, verifying carrier rates, or building a load, having instant access to freight class information keeps you competitive. Many brokers have lost margins to reclassification fees simply because they estimated class instead of calculating it.

For shippers, understanding freight class helps you optimize packaging and palletization. Sometimes, a small change in how you stack or package products can shift you into a lower freight class, saving significant money over hundreds of shipments. This is especially important for e-commerce businesses shipping via LTL.

Our calculator uses the standard NMFC density-to-class mapping that carriers across the industry follow. While some commodities have specific class assignments regardless of density (like furniture or electronics), the density calculation covers the majority of general freight shipments.