Freight class
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Instantly calculate freight class and density

Shipping less than truckload (LTL) freight, means you’ll likely need a National Motor Freight Classification (NMFC) number. This measurement helps ensure standard prices across LTL carriers and businesses. Density is one of the most important factors used to determine your freight class.

Our easy-to-use freight density calculator can help you verify density and choose the right freight class to accurately plan your shipment.

Enter your shipment details to see the density of your freight and recommended freight class:

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Freight class reference chart

Freight Density (in lbs per cubic foot) Freight Class
Less than 1 400
1 but less than 2 300
2 but less than 4 250
4 but less than 6 175
6 but less than 8 125
8 but less than 10 100
10 but less than 12 92.5
12 but less than 15 85
15 but less than 22.5 70
22.5 but less than 30 65
Over 30 60

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Freight class without the frustration

Not sure what freight class your shipment falls into? No problem! We’ll guide you through the process and calculate it for you as part of your comprehensive shipping quote.

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How to calculate freight density

  1. 1. Measure the total cubic inches of your shipment (length x width x height).
  2. 2. Convert that total to cubic feet (divide by 1,728 for quick conversion).
  3. 3. Determine the weight of the shipment in pounds.
  4. 4. Divide the total weight by total cubic feet of the shipment to get the lbs/ cubic ft (as shown in the reference chart above).

If you have several different pieces, complete the calculation steps above for each individual piece. Add the cubic inch measurements for the pieces together to get the grand total, then convert to cubic feet for a grand total before dividing by weight.

Skip the math and rely on Freightquote

Remember these class codes are estimates. Reduce the risk of miscalculations, and save time by using our online tool to quote and book your shipments. Simply input your shipment’s accurate measurements and weight and we'll deliver quotes based on your shipment’s freight density.

No freight scale? No problem.

Check out these creative ideas to accurately measure weight without a freight scale.

How density affects your freight rate

Density is based on a shipment's dimensions and weight. It is one factor that influences freight classification. Typically, a shipment with lower density has a higher freight classification. Typically, lower freight classes mean lower prices for freight shipping.

Factors that determine freight classification

The NMFC system standardizes how commodities are classified and is based on four main factors:

  1. 1. Density (most important): Both the space the items take up in the trailer and the weight of the item factors into the density calculation.
  2. 2. Stowability (important): Items that are more difficult to store will be given a higher freight class. This includes shipments that might be hazardous or very heavy.
  3. 3. Handling (important): Any freight that requires special handling could be assigned a higher class.
  4. 4. Liability (less important): Perishable freight or freight that could be easily damaged will be designated a higher freight class.
  5. Remember, the NMFC codes are regularly updated, and specific commodities are assigned class numbers based on industry standards and regulations.

Freightquote online tool example of freight classification

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No need to memorize all the different freight classes—our guided online quoting tool will estimate your freight class based on the weight and dimensions you provide. We make your shipping experience as easy as possible.

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Freight class FAQ

Why is freight class important?

There are a few reasons why freight class is important:

  1. 1. Sets standards: Carriers can easily determine the shipping cost. In turn, shippers can more easily compare shipping rates from different carriers.
  2. 2. Reduces shipping costs: By determining the correct freight class for a commodity, shippers can avoid being charged more for shipping.
  3. 3. Ensures accuracy: Freight class is used to determine the level of liability for a shipment. This means if a shipment is damaged during transit, the insurance company will be able to determine how to fairly compensate the shipper.

What happens if my freight class is wrong?

If your freight class is wrong, you may be charged more for shipping. In some cases, you may also be subject to a reclassification fee. This is a fee the carrier charges for reclassifying your shipment.

Reduce the risk of classification adjustments by using our online booking tool, using our freight class calculator, or working with one of our shipping experts.

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