Tools to calculate freight class on your own

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Tools to Calculate Freight Class on Your Own 

Freight classes and subclasses are a critical part of obtaining an accurate LTL shipping quote for your shipment, but they can be complicated and require precision and attention to detail. Depending on the specific nature of a product, the freight class code can fall anywhere within an extensive range of classes and subclasses. Because of this, it is imperative to know not only the correct NMFC code for the item but also the applicable subclass into which it fits in order to assign the correct freight class. Today we will be looking at some of the tools and processes you can use to accurately determine the freight class of your LTL shipment.


What is NMFC Freight Class?

National Motor Freight Classification (NMFC) is a freight classification system established by the National Motor Freight Traffic Association (NMFTA) and applied to all LTL cargo. NMFC codes provide universal standardized freight classes that identify the transportability of many different types of goods being shipped together in LTL shipments. Because LTL shipping involves shipments containing a variety of different products with different densities, liabilities, safety restrictions, and handling considerations all transported together in a single load, freight class codes are necessary to provide standards upon which shippers, 3PLs, and carriers can negotiate shipping rates. 

There are 18 possible NMFC classifications for LTL freight, the lowest and least expensive being 50, and the highest and most expensive being 500. LTL freight that is dense, sturdy, and has less liability will be classified lower, while freight that is fragile, uniquely or awkwardly shaped, or prone to damage, loss, or theft will be classified higher. Typically, the denser an item, the lower its freight classification code. NMFC freight classes are composed of thousands of individual items, each with its own NMFC code and subclass assigned based on what it is, its dimensions, how it is packaged, whether it is assembled or disassembled, the materials from which it is made, and other considerations. Once you find your item and its corresponding code, the code will tell you which of the eighteen classes it falls under, giving you your official NMFC freight class. Simple, right?


What Tools Do You Need to Determine Freight Class on Your Own?

The key to determining an accurate freight class for your items on your own is using the right tools. Precisely measuring and weighing your goods, consulting the NMFC code list on the NMFTA’s website, and knowing how to calculate the density of your freight properly can all help you accurately assess the freight class of your LTL shipment.


Correct Weights and Dimensions 

The first step toward figuring out the proper freight class of your shipment is taking accurate weights and measurements. You can measure your freight by hand, or there are several technologies that can add accuracy and speed to this process.

When measuring a shipment by hand, determine its length, width, and height, including its packaging. If an object is irregularly shaped, measure it as if it is in a rectangular box, using its most extreme points to record the dimensions. If a shipment has multiple pieces, do this process for each. Determine the shipment’s weight using a large enough scale to fit the entire load and all necessary packaging, pallets, or skids. 

To speed up this process, shippers can use forklift scales or automated cubing solutions like dimensionalizers that, when paired with a scale, can accurately make a record of each shipment that includes photos, measurements, and weight in a few seconds.

Once you have an accurate weight and measurement, you can use it to look up a commodity’s freight class, and if it is not listed, calculate its freight density to determine the correct freight class. 


NMFC code list 

The National Motor Freight Traffic Association (NMFTA) publishes a list of freight class designations, codes, and subclasses for commonly shipped items ( Shippers can look up their items in the NMFC guide by their descriptions to find the corresponding freight class. However, while the NMFC codebook provides the freight class and item code for many commodities, it cannot encompass the millions of different items and their variations being shipped every year.


Freight Density Calculator

Finding the exact NMFC code and subclass corresponding to one of the eighteen different freight classes is the most precise way to correctly classify your cargo and avoid a reclassification rebill from your carrier. But not every item is on the NMFC list with a corresponding code and subclass. When this is the case, the calculated density of the item is used to determine its freight class. 

If the commodity in your LTL freight shipment is not listed within the NMFC codes, you can apply a general class rate or NOI (Not Otherwise Indicated) class to determine the cost to ship the item. Most carriers will manually process NOI freight items and apply a quote based on the item’s density or pounds per cubic foot (PCF). It is strongly recommended that shippers take exact measurements for the weight and dimensions of their shipment so as to provide the most accurate PCF possible to the carrier to avoid any discrepancies that could lead to reclassification or rebills. The PCF density of an item can be determined simply by dividing the item’s volume in cubic feet by its gross weight in pounds. Again, note that the dimensions measured should include the total size of the shipment, including packaging and pallet. 

For example:

The volume of an item on a pallet with dimensions 36 inches long x 36 inches wide x 36 inches high = 48" x 48" x 48" / 1,728* = 64 cubic feet. 

(*note that 1,728 is the number of cubic inches in a cubic foot)

If the actual gross weight of the goods is 400 pounds, then the calculated density of the goods is 400 pounds / 64 cubic feet = 6.25 pounds per cubic foot. This would place the item to be shipped in freight class 125*.

*This calculation is an estimate only. Density is the main factor for determining freight class, but other transportability factors such as handling, stowability, and liability can change the item’s final freight classification. Contact Koho for help deciding the freight class of your shipment.

Freight class is designed to identify an item’s overall transportability. In LTL shipping, space is limited, and cargo configuration on a trailer is critical to a carrier’s profitability, so weights, measurements, and calculations must be accurate to avoid future rebills from carriers due to reweighs and reclassifications. Bottom line, accuracy is essential, so invest in practices, equipment, and a 3PL partner like Koho that can help you get the right LTL rate the first time.

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