Freight Classes and Dimensional Weights

With the recent addition of KFS-Jacksonville, an expedited trucking specialty branch, we decided to focus this week on the basic rules and information regarding freight classes and dimensional weight calculations. Freight classes are a vital part of both trucking and air freight (and in many cases consolidated ocean cargo) and understanding how to classify your shipments will help avoid costly penalties for reclassification and corrections.

What is Freight Class?

Freight classes are standards to advise the standard pricing on a shipment regardless of carrier, warehouse, or broker. They are defined by the National Motor Freight Traffic Association and through the NMFC. There are 18 possible classes, with Class 50 being the least expensive and Class 500 being the most expensive.

How is Freight Class Determined?

Freight Class is determined by four factors.

We can help.

  1. Dimensions + Weight = Density and Value. The density of an item is calculated by dividing the weight of the item in pounds by its volume in cubic feet. A 100lb box with the dimensions 26”x26”x26” would have a density factor of 9.83 and a dimensional class of 100. The formula is POUNDS / [(L”xW”xH”) /1728] so here we have 26x26x26=17576 which is divided by 1728 which is 10.1713 and then the 100 pounds divided by 10.1713 give us 9.83.
  2. The way freight can be transported. Is the cargo hazardous? Oversized? Overweight? Non-Stackable? While most freight is fine for trucking, some cargo is more difficult to arrange.
  3. Fragile, oddly shaped, or hazardous cargo can require special handling.
  4. Could your cargo damage surrounding cargo during transport? Is there a high potential for theft? Is the cargo perishable?

Dimensional weight and freight class can be confusing for shippers, considering it’s more than just the weight and piece count that matters when declaring this information. An incorrect freight class can cause a reweigh/redim that most companies charge for while also applying the higher class rate to the shipment and delays in delivery due to the time it takes to rework the cargo. It is always better to make sure your freight is correctly classified the first time. KFS is here to help you navigate the information on your freight. We offer support services for both trucking and air/ocean cargo in our offices and will make sure the information you’re using is exactly right preventing you from overpaying on a class that is too high or dealing with fees and delays from a class that is too low.


Pounds per Cubic Foot Class
< 1lb 500
>1 but < 2 400
>2 but < 3 300
>3 but < 4 250
>4 but < 5 200
>5 but < 6 175
>6 but < 7 150
>7 but < 8 125
>8 but < 9 110
>9 but < 10.5 100
>10.5 but < 12 92.5
>12 but < 13.5 85
>13.5 but < 15 77.5
>15 but < 22.5 70
>22.5 but < 30 65
>30 but < 35 60
>35 but < 50 55
50 + 50