Freight Density

Freight density is the ratio of a shipment's weight to its volume, expressed in pounds per cubic foot (PCF). It's calculated by dividing the total shipment weight by its total cubic dimensions. A pallet measuring 48" x 40" x 48" weighing 1,200 pounds has a density of about 21.4 PCF. This number is the single most important factor in determining freight class – and by extension, the LTL rate a shipper pays.

Higher density means lower freight class and lower cost per hundredweight. Dense, heavy freight is efficient for carriers – it fills trailers by weight without wasting cubic space. Light, bulky freight is the opposite: it takes up trailer space that could carry more revenue-generating weight, so carriers charge more per pound to compensate. This is why freight class runs inversely to density: class 50 (cheapest) is the densest freight, and class 500 (most expensive) is the lightest.

Density-based pricing means that product packaging decisions directly affect transportation cost. A shipper who can redesign packaging to stack higher, reduce void space, or increase unit density can shift freight class downward and reduce LTL costs – sometimes significantly. Conversely, shippers who don't know their actual freight density risk misclassifying shipments and facing reclassification charges when carriers inspect and measure the freight at their terminals.

Accurate density calculation requires knowing exact product dimensions and weights at the SKU level, then aggregating to the pallet or shipment level. Shippers who maintain a detailed item master – with actual measured dimensions, not estimates – avoid the density guessing game that leads to misclassification, invoice disputes, and overpayment.