What is Freight Class?

Freight class is a standard classification system for shipments, defined by the National Motor Freight Traffic Association (NMFTA). It's used to categorize commodities like Aluminum for transport, taking into account factors like weight, dimensions, density, storage capability, ease of handling, and liability. Freight class is a system to categorize different types of goods being shipped.

How to determine Freight Class

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Density is a key concept in freight shipping, as it significantly impacts the freight class for commodities like Aluminum and hence, the shipping cost. It is calculated as the weight of the shipment divided by its volume. In freight terms, density is a measure of how much space an item occupies relative to its weight.

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Stowability is used in freight shipping to describe how easily an item can be stowed or stored in relation to other items. For example, when trying to understand stowability for Aluminum, it is important to know if the item can be packaged efficiently and stowed onto the truck easily. In other words- It's a measure of how well freight can be accommodated with other freight in a shipment.

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Liability is a term used to refer to the accountability or risk involved in transporting Aluminum. It's one of the factors considered when determining freight class. It's the carrier's responsibility for the condition of goods during transport.

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Handling refers to the procedures and precautions taken when moving and storing Aluminum. It is one of the factors considered when determining freight class for Aluminum. It's the precautions taken when moving and storing freight.

Freight Class Commodities


Aluminum Sheet NOI

Molding NOI In Packages

Screws In Boxes




Common Commodity Items



For many NMFC® codes there isn’t just one single class that is applied. Often, NMFC® numbers have multiple "sub-classes", which are almost always based on the density of the shipment. In the instance where your NMFC® number has multiple sub classes, it's best to contact an expert, like Koho, to help identify which subclass to use.


How do I get my NMFC code?

An organization known as the National Motor Freight Traffic Association (NMFTA) publishes a list of freight class designations, codes, and subclasses for many commonly shipped commodities ( You must pay a subscription fee to view this list. For more information about freight classes for free on our freight classes pages.

What is the purpose of freight classification?

Freight classification groups products based on similar density, stowability, handling and liability so carriers and shippers have an effective way of communicating the ease of transporting said freight.