Freight class calculator

The National Motor Freight Classification sorts LTL freight into 18 classes from 50 to 500. Class 50 is dense, durable, easy-to-handle freight and costs the least to ship. Class 500 is light and bulky and costs the most. The class goes on the bill of lading and drives the rate.

Start with density. Multiply length × width × height in inches and divide by 1,728 to get cubic feet. Then divide the total weight in pounds by those cubic feet. That pounds-per-cubic-foot figure maps onto the NMFTA density table: 50 lb/ft³ and up is class 50, under 1 lb/ft³ is class 500.

No, and this is where shipments get re-classed. The NMFC weighs four characteristics: density, stowability, ease of handling, and liability (value, fragility, hazard, theft appeal). Many commodities also carry a specific NMFC item number that fixes the class regardless of density. Density is the right starting point and the wrong final word. Confirm with your carrier before the BOL goes out.

The carrier reweighs and remeasures at the terminal, re-classes the shipment, and bills the difference, usually with an inspection fee on top. Understating class is the most common source of LTL billing disputes.

The pallet. Use outside dimensions including packaging and the pallet itself, and gross weight including both. That’s what gets measured at the dock.