# How to calculate Freight Density: OpenBorder Freight Density Calculator

What is Freight Density?

Freight Density is a key deciding factor in the NMFC Freight class assigned to an item. It is useful to understand the freight density of a shipment to correctly estimate the price.

How does Freight Density affect my Freight Class?

As the freight density goes up, the freight class goes down. The logic behind this is the physical space an item takes up in a truck. Higher density items, while heavy, are small and compact so they don’t take up as much area, causing the shipment cost to decrease.

When should you use Freight Density?

Freight Density is not always used to determine freight class. Typically, density is needed when size and quantity vary between shipments. The item in question has to be either density based, or fall into the category known as Not Otherwise Indicated (NOI). Density based class is when the NMFC code based on item type is not adequate in determining class. NOI means that there is no NMFC number associated with the item at all.

For example, if your item falls under the paper categories and the adhesives subcategory, it will automatically be assigned a freight class of 77.5 without requiring the freight density.

How to calculate Freight Density?

Freight density is based on the dimensions of the item.

The formula for freight density is:

(Length × Width × Height) ÷ 1728 = Cubic Feet (CU FT)

Weight (Pounds)/CU FT = Density in pounds per Cubic Foot (#PCF)

1) Measure the length, width, height of the item.

2) Multiply the dimensions (length x width x height).

3) To find cubic feet of the shipment, divide this by 1,728 (cubic inches per foot).

4) Finally, divide the weight of the shipment by the total cubic feet to find your freight density, or pounds per cubic foot (#PCF).