Freight Class Calculator (NMFC)
Calculate NMFC freight class from shipment density.
Determines LTL shipping rates — the most misunderstood factor in freight pricing.
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 determining your base LTL shipping rate — get it wrong and you face expensive reclassification charges after delivery.
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 fills by volume before it reaches weight limits in most cases. A pallet of feather pillows might weigh 80 lbs but take up 40 cubic feet — the carrier could have fit a much heavier (and more profitable) shipment in that space. Freight class compensates carriers for the space taken by low-density goods.
Density-Based Class Lookup The NMFC density thresholds are: 50+ lbs/cu ft = Class 50, 35–50 = Class 55, 30–35 = Class 60, 22.5–30 = Class 65, 15–22.5 = Class 70, 13.5–15 = Class 77.5, 12–13.5 = Class 85, 10.5–12 = Class 92.5, 9–10.5 = Class 100, 8–9 = Class 110, 7–8 = Class 125, 6–7 = Class 150, 5–6 = Class 175, 4–5 = Class 200, below 4 = Class 250 or higher.
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.