Freight Class Calculator (NMFC)

What Is NMFC Freight Class? The National Motor Freight Classification (NMFC) is a standardized system developed by the National Motor Freight Traffic Association (NMFTA) that categorizes LTL (Less Than Truckload) freight into 18 classes ranging from Class 50 to Class 500. The class is the single most important factor setting your base LTL rate. Get it wrong and the carrier reclassifies the shipment after delivery, then bills the difference plus a fee, which is a bill nobody has budgeted for.

The 18 NMFC Classes Classes range from 50 (cheapest to ship) through 500 (most expensive): 50, 55, 60, 65, 70, 77.5, 85, 92.5, 100, 110, 125, 150, 175, 200, 250, 300, 400, 500. Class 50 covers dense, durable, well-packaged goods like steel bars, cast iron, and sand. Class 500 covers extremely low-density items like ping pong balls, styrofoam blocks, or assembled furniture with lots of empty space.

The Four Factors NMFC classification considers four factors, with density being primary. Density (weight per cubic foot) is the main driver and what this calculator uses. Stowability: can the shipment be stacked? Irregular shapes that can’t be stacked go to a higher class. Handling: does the shipment require special equipment, extra care, or create unusual difficulty? Liability: is the shipment high-value, fragile, or susceptible to damage or theft?

Why Density Matters So Much A carrier’s truck usually fills by volume long before it reaches its weight limit. A pallet of feather pillows might weigh 80 lbs and take up 40 cubic feet, and the carrier could have put a far heavier, far more profitable shipment in that same space. Freight class is how they get compensated for it.

Density-Based Class Lookup The NMFC density thresholds, in pounds per cubic foot, run the full 18 classes:

The bottom four rows matter more than they look. A shipment at 2.5 PCF is Class 300, not “250 or higher”, and the gap between 250 and 300 is real money on a long haul.

Important Caveat Many commodities have an assigned NMFC item number with a specific class that overrides the density calculation. Automobiles, electronics, pharmaceuticals, and many other categories have assigned classes regardless of actual density. Always verify with the NMFTA directory or your broker for regulated commodity classes.