Many businesses that offer transportation management services provide free lists of NMFC freight classifications on their websites. The National Motor Freight Transportation Association also offers an in-depth guide to the NMFC that can be purchased at NMFTA.org or accessed through ClassIT.
The National Motor Freight Classification or NMFC is a standard that allows carriers and shippers to quickly negotiate shipping costs. This standard evaluates transported materials based on four characteristics: density, handling, stowability and liability for theft and spoilage. There are a total of 18 NMFC freight classes as of 2015, with Class 50 being the least expensive, and Class 450 being the most expensive.