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NMFTA Freight Class: Understanding NMFC Codes

Freight class is key to shipping and receiving goods efficiently. We often see freight class used in LTL (less-than-truckload) shipments, as it helps determine prices using a volume based numeric system to categorize freight. Whether you’re transporting something big or small, knowing freight classes is important. Just like people, freight comes in all sizes and shapes, and trusting the wrong mode of transport could result in lots of damage to precious cargo.NMFTA NATIONAL MOTOR FREIGHT TRAFFIC ASSOCIATION CARGO FREIGHT CLASS CALCULATIONS When it comes to shipping things, most people think of the big picture – i.e., where you’re getting something shipped and the delivery times. But more often than not, shippers are more concerned about where you’re planning on putting the goods on your truck, as well. When it comes to LTL shipping, freight class is significant. The classification system is a way to get your head around how much volume fits in available space and improve the transport of goods.


Freight class is a standard used in the shipping industry to group or categorize freight for transport. It is determined using a guideline set out by the NMFTA (National Motor Freight Traffic Association) to provide a fair standard for price comparison and determine goods' transportability. The class system helps when pricing freight and gives shippers a fair rate based on a general standard. The class system also keeps goods safe and free from damage which could result from improper transport practices. However, in order to determine freight class, several factors need to be considered.


In order to classify freight, you would look at density, liability, handling and stowability.  As a general rule, items which are lighter and easier to handle or transport tend to cost less and they are categorized in the lower freight classes. If you have an item like bricks or hardwood floors, this would be a lower freight class, unlike a flat screen TV which is more complicated to transport and lower density, thus higher freight class. High value items or those which are complicated to ship and are higher freight class, so they will cost more. 

Freight class is determined by NMFC (National Motor Freight Classification) using four main categories: 


Using pounds per cubit foot, density determines the space that an item would occupy in relation to the weight of the item. Higher density items are easier to ship as they are more compact, and tend to be less expensive to ship as a result. In order to determine the density of freight, you would take the total cubit feet and divide by total weight (lbs).

Calculate Freight Density:

  1. Find length, width and height in inches, of your shipment (with packaging).
  2. Multiply them to find the size in cubic inches.
  3. Divide by 1, 728 (cubic inches in 1 foot) to determine feet 
  4. Divide total freight weight (lbs) by the cubic feet total to get density.


Since the carrier assumes responsibility for the items when they're shipped, those items of high liability cost more to ship since they require special handling. The value of the item as well as fragility matters, as items which are high risk or high value, such as those potentially easily damaged, tend to be more expensive to ship, because they are more likely to be stolen or incur damage.


Stowability looks into how easy it is to transport the freight, by looking at how the goods fit into the transport container or truck and whether they can be transported with other goods. If freight is able to be transported with other commodities, then it is cheaper to ship. Hazardous or special items tend to be more expensive, because they have to be shipped separately due to regulations. If freight needs to be temperature controlled or cannot mix with other goods, then it will be higher class and cost.


How easily an item is handled also determines freight class. If an item is fragile or requires special handling then it will cost more. Hazardous or fragile materials fall into this category, as there may be more difficulty in the handling of the freight. This applies to non-uniform goods as well as hazardous materials and products which require more handling.    


Class 55 Over 50lbs per cubic foot
Class 60 30-35lbs per cubic foot 
Class 65 22.5-30lbs per cubic foot
Class 70 15-22.5lbs per cubic foot
Class 77.5 13.5-15lbs per cubic foot
Class 85 12-13.5lbs per cubic foot 
Class 92.5 10.5-12lbs per cubic foot
Class 100  9-10.5lbs per cubic foot
Class 110 8-9lbs per cubic foot
Class 125 7-8lbs per cubic foot
Class 150 6-7lbs per cubic foot
Class 175 5-6lbs per cubic foot
Class 200 4-5lbs per cubic foot
Class 250 3-5lbs per cubic foot
Class 300 2-3lbs per cubic foot
Class 400 1-2lbs per cubic foot
Class 500 Less than 1lb per cubic foot
  • Lower Density = Higher Freight Class
  • Higher Freight Class = Higher Cost 
  • Class 500 = Most Expensive
  • Class 55 = Least Expensive 

Knowing the freight class of your shipment will help you ensure that you’re not overpaying for transportation costs, and that you’re getting the best possible rate. You should know the freight class before contacting freight carriers to make sure you’re able to negotiate the best price for your shipment. Carriers are also able to know the risks associated with each shipment, and ensure a fair rate as well. There are a lot of options when it comes to freight class, so get the information you need to make sure you are saving money where it counts.