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Freight Class Calculator

Enter your pallet dimensions and total weight to get shipment density in pounds per cubic foot and the estimated NMFC freight class — the same density brackets carriers use when they re-rate a shipment on the dock.

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Estimate only. This uses the standard density brackets and assumes a density-based NMFC item applies. Many commodities are classified under a fixed, named NMFC item regardless of density, or use different brackets under a specific item number — always confirm the actual applicable NMFC item and sub-number before booking.

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How freight class is calculated

For any commodity classified on density, freight class comes from a single number: pounds per cubic foot. You get there in two steps.

1 · Cubic feet(Length × Width × Height in inches ÷ 1,728) × pieces
2 · DensityTotal weight in pounds ÷ total cubic feet

Measure the packaged, palletised freight — pallet included, plus any overhang. Carriers measure the outside of what actually sits on their dock, not the product inside the box. A shipment that measures 48″ × 40″ × 36″ is 40 cubic feet; at 850 lb that is 21.25 lb/ft³, which sits in the 15-to-22.5 bracket — class 70.

Density to freight class table

The 18 NMFC classes and the density bracket each one corresponds to. Denser freight takes a lower class, and a lower class generally means a lower rate per hundredweight.

Density (lb/ft³)Freight class
50 and over50
35 – under 5055
30 – under 3560
22.5 – under 3065
15 – under 22.570
13.5 – under 1577.5
12 – under 13.585
10.5 – under 1292.5
9 – under 10.5100
8 – under 9110
7 – under 8125
6 – under 7150
5 – under 6175
4 – under 5200
3 – under 4250
2 – under 3300
1 – under 2400
Less than 1500

These are the standard density brackets. A commodity governed by a named NMFC item may carry a fixed class or its own brackets — see the FAQ below.

Freight class questions

How do you calculate freight class?

Freight class is most often driven by density. Multiply length × width × height in inches, divide by 1,728 to get cubic feet per piece, then multiply by the piece count. Divide the shipment's total weight in pounds by that cubic footage to get density in pounds per cubic foot, then read the density against the NMFC density brackets — the denser the freight, the lower the class and generally the lower the rate.

What is the formula for freight density?

Density (lb/ft³) = total weight in pounds ÷ total cubic feet, where total cubic feet = (length × width × height in inches ÷ 1,728) × number of pieces. Always measure the outside of the packaged, palletised freight — including the pallet itself and any overhang — because that is what the carrier measures on the dock.

Does density always determine freight class?

No, and this is the most common and most expensive misunderstanding. The NMFC classifies commodities on four factors: density, stowability, handling, and liability. Many commodities are assigned a fixed class under a named NMFC item regardless of how dense the shipment is, and others use brackets specific to that item number. A density calculation is a reliable estimate only when a density-based item genuinely applies, so confirm the actual NMFC item and sub-number before booking.

What are the 18 LTL freight classes?

There are 18 classes: 50, 55, 60, 65, 70, 77.5, 85, 92.5, 100, 110, 125, 150, 175, 200, 250, 300, 400 and 500. Class 50 is the densest and cheapest to ship; class 500 is the lightest and most expensive per pound.

What happens if I put the wrong freight class on a bill of lading?

The carrier will typically reweigh or re-measure the shipment on the dock, reclassify it, and issue a corrected invoice for the difference — often with an inspection or reclassification fee on top. Because the correction arrives after delivery, it usually lands as an unexpected charge weeks later, which is why getting class right at the point of quoting matters more than fixing it afterwards.

Is freight class the same as dimensional weight?

No. Freight class is an NMFC concept used in LTL trucking, and dimensional weight is a parcel-carrier concept. Both penalise light, bulky freight, but they are calculated differently and are not interchangeable. An LTL carrier prices from class and actual weight, not from a dimensional weight figure.

Keep reading

Get the classification right every time

Density is one of four factors the NMFC uses, and the one people over-rely on. The full certification course covers classification, rating, carrier rules, claims and audit — with a verifiable certificate at the end.

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