Freight Class Calculator
Density-based guidance only. The NMFC changed its classification rules in 2025 and many items have their own class, so confirm with your carrier before you book.
How the freight class calculation works
Estimate an LTL shipment's freight class from its size and weight with the density-based class table, then confirm it with your carrier.
Measure each unit and multiply
A 48 × 40 × 48 in pallet is 92,160 cubic inches. Measure to the widest and highest points, pallet included.
Convert to cubic feet
Divide by 1,728: 92,160 ÷ 1,728 = 53.33 cubic feet. Multiply by the number of identical units.
Divide weight by cubic feet for density
500 lb ÷ 53.33 ft³ = 9.38 lb per cubic foot.
Read the class from the density table
9.38 lb/ft³ falls in the 8 to under 10 band, which is class 100. Denser freight gets a lower class and usually a lower rate.
Worked example. One 48 × 40 × 48 in pallet weighing 500 lb takes up 53.33 cubic feet. Its density is 9.38 lb per cubic foot, which gives class 100 on the density-based table.
Freight Class FAQ
How do I calculate freight class?
Multiply length × width × height in inches, divide by 1,728 to get cubic feet, then divide the weight by the cubic feet. Look up that density in the class table: 9.38 lb/ft³ is class 100.
What is freight class?
Freight class is the rating the National Motor Freight Classification (NMFC) gives LTL freight, from class 50 to class 500. It is based on four things: density, handling, stowability and liability. Dense, easy-to-handle freight gets a lower class and usually a lower rate.
What is the freight class density chart?
The NMFC 13-sub density scale: under 1 lb/ft³ is class 400; 1 to under 2 is 300; 2 to under 4 is 250; 4 to under 6 is 175; 6 to under 8 is 125; 8 to under 10 is 100; 10 to under 12 is 92.5; 12 to under 15 is 85; 15 to under 22.5 is 70; 22.5 to under 30 is 65; 30 to under 35 is 60; 35 to under 50 is 55; 50 or more is class 50.
What changed in the NMFC in 2025?
Docket 2025-1, effective 19 July 2025, made density the main factor for many items and expanded the density scale from 11 to 13 steps. The new top steps give class 55 for 35 to under 50 lb/ft³ and class 50 for 50 lb/ft³ or more. Items with handling, stowability or liability issues may not use the full density scale, so check your item's NMFC number.
What is the lowest and highest freight class?
Class 50 is the lowest, for freight of 50 lb per cubic foot or more on the density scale. The NMFC runs up to class 500. On the 13-sub density scale, the highest class is 400, for freight under 1 lb per cubic foot.
How is freight class worked out for several pallets?
The NMFC calculates density for each handling unit. If the bill of lading shows only a total weight, density may be worked out from the total weight and total cube. This calculator assumes identical units, so both methods give the same answer: two 48 × 40 × 48 in pallets at 1,000 lb in total are 9.38 lb/ft³, class 100.
Does pallet weight count toward freight class?
Yes. Density uses the shipped weight and outside dimensions, so the pallet and packaging are included in both.
Why did my carrier change my freight class?
Carriers inspect and re-weigh freight. If the measured density or the NMFC item differs from the bill of lading, they reclassify it and bill the difference.
Sources: NMFTA: FCDC 13-sub full scale density table (ClassIT+ documentation) · NMFTA: density and class breaks for the 13-sub structure · NMFTA: how the density of a handling unit is calculated · NMFTA: what is a freight class?