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Freight Class Calculator

Enter your shipment's dimensions and weight to estimate its NMFC freight class from density, using the 2025-1 13-tier scale.

SHIPMENT PIECES
DENSITY9.4 lb/ft³
ESTIMATED CLASS100NMFC density-based
TOTALS500 lb · 53.3 ft³
DensityFreight class
≥ 50 lb/ft³Class 50
≥ 35 lb/ft³Class 55
≥ 30 lb/ft³Class 60
≥ 22.5 lb/ft³Class 65
≥ 15 lb/ft³Class 70
≥ 12 lb/ft³Class 85
≥ 10 lb/ft³Class 92.5
≥ 8 lb/ft³Class 100
≥ 6 lb/ft³Class 125
≥ 4 lb/ft³Class 175
≥ 2 lb/ft³Class 250
≥ 1 lb/ft³Class 300
≥ 0 lb/ft³Class 400

Density-based estimate. Some commodities keep NMFC-specific classes regardless of density — confirm the final class with your carrier or the NMFC ClassIT tool.

How freight class is estimated

Under the NMFC 2025-1 density scale, freight class is derived from density in pounds per cubic foot. Lower-density (bulkier, lighter) freight gets a higher, more expensive class; higher-density (compact, heavier) freight gets a lower, cheaper class. This calculator applies the density scale directly — some commodities still carry NMFC item-specific classes regardless of density, so always confirm with your carrier before booking.

Density (lb/ft³) = total weight (lb) ÷ total volume (ft³)
What is freight class?

Freight class is an NMFC (National Motor Freight Classification) code from 50 to 400 that LTL carriers use to price a shipment. Since the 2025-1 revision, most commodities are classed on a 13-tier density scale rather than commodity-specific rules — denser cargo gets a lower (cheaper) class.

How do I calculate freight density?

Density in lb/ft³ is total weight divided by total volume: add up each piece's weight, add up each piece's volume in cubic feet (length × width × height in inches ÷ 1728, times quantity), then divide total pounds by total cubic feet.

What happens if I declare the wrong freight class?

Carriers can reweigh and reclass a shipment at inspection. If your declared class is too low for the actual density, you'll be billed a reclassification fee plus the corrected freight charge — so it's cheaper to estimate accurately upfront than to under-declare.

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