For a mixed pallet classified by density, everything starts with how much space it takes up. Length, width, and height give you the cubic volume, and that volume gets paired with the pallet’s weight to work out density in pounds per cubic foot.
NMFC Docket 2026-2 puts more focus on this density-based approach for certain mixed shipments. Once you have the pallet’s density, the freight class chart shows which NMFC class corresponds to that density range.
What Is a Freight Class Chart?
A freight class chart shows how density connects to freight class. Once you know the pallet’s density in pounds per cubic foot, you find that number on the chart and see which NMFC class it falls into.
The NMFC density scale has 13 ranges, starting at Class 400 for freight below 1 lb/ft³ and going down to Class 50 for freight at 50 lb/ft³ or more.
For a mixed pallet, the chart applies when the shipment is being classified using density under the relevant NMFC provision.
Why Is the NMFC Density Scale Relevant under NMFC Docket 2026-2?
The 13-tier NMFC density scale was already being used before Docket 2026-2 came out. Docket 2025-1 expanded the older 11-tier version by adding Classes 60, 55, and 50.
So Docket 2026-2 is not introducing a new density scale. What changes is where the existing 13-tier scale is proposed to be used, including certain mixed shipments under Item 640. That is why this freight class chart comes into the picture for mixed pallets.
Which Freight Class Applies to Each NMFC Density Range?
The NMFC freight class chart has 13 density ranges. Find the pallet’s density in the left column, and the freight class is listed next to it.
| Density in lb/ft³ | Freight Class |
|---|---|
|
Less than 1 |
400 |
|
1 but less than 2 |
300 |
|
2 but less than 4 |
250 |
|
4 but less than 6 |
175 |
|
6 but less than 8 |
125 |
|
8 but less than 10 |
100 |
|
10 but less than 12 |
92.5 |
|
12 but less than 15 |
85 |
|
15 but less than 22.5 |
70 |
|
22.5 but less than 30 |
65 |
|
30 but less than 35 |
60 |
|
35 but less than 50 |
55 |
|
50 or greater |
50 |
As density goes up, the class number comes down. Freight below 1 lb/ft³ falls under Class 400, while freight at 50 lb/ft³ or more falls under Class 50.
To know where a mixed pallet sits on this chart, you first need its density.
How Is Density Calculated Before Using the Freight Class Chart?
Before you get to density, you need to know how much space the pallet takes up.
For a mixed pallet being classified by density, you need its cubic volume and weight to calculate its density. NMFTA states that cubage is based on the greatest straight-line length, width, and height of the handling unit, including any projections, as presented for shipment.
How do you calculate pallet cube?
Multiply the pallet’s length, width, and height in inches. Divide that number by 1,728 to get the volume in cubic feet.
Cube = Length × Width × Height ÷ 1,728
For a mixed pallet measuring 48 × 40 × 48 inches:
48 × 40 × 48 = 92,160 cubic inches
92,160 ÷ 1,728 = 53.3 ft³
How do you calculate pallet density?
Once you have the cube, divide the pallet’s weight by that number.
Density = Weight ÷ Cube
For a 500 lb pallet with a cube of 53.3 ft³:
500 ÷ 53.3 = 9.4 lb/ft³
The density here is 9.4 lb/ft³. You then check where 9.4 falls on the freight class chart.
NMFTA also uses this same method for handling-unit density: weight divided by cubic feet.
How Do You Match Pallet Density to the Correct Freight Class?
Once you have the pallet’s density, check which range it falls into on the freight class chart. The class listed for that range is the one that matches the calculated density.
Example 1: Lower-density mixed pallet
Using the 48 × 40 × 48-inch, 500 lb mixed pallet from the earlier example, the density comes to 9.4 lb/ft³.
On the chart, 9.4 falls in the 8 but less than 10 lb/ft³ range. That puts the pallet at Class 100.
Example 2: Denser mixed pallet
Now consider the same mixed pallet at 48 × 40 × 48 inches, but with a weight of 900 lb. The cube is 53.3 ft³.
900 ÷ 53.3 = 16.9 lb/ft³
On the chart, 16.9 falls between 15 and 22.5 lb/ft³. That puts the pallet at Class 70.
The pallet takes up the same amount of space in both examples, but the heavier pallet has a higher density and a lower freight class. That difference becomes easier to understand when you look at how density and freight class move in opposite directions.
Why Does a Denser Pallet Usually Have a Lower Freight Class?
In the two mixed-pallet examples above, the pallet size stays the same while the weight changes. The 900 lb pallet packs more weight into the same amount of space. That gives it a higher density.
The NMFC density scale assigns higher class numbers to freight with lower density and lower class numbers as density increases. So a pallet that takes up more space for its weight sits higher on the class scale, while a denser pallet sits lower.
| Pallet Type | Density | Freight Class |
|---|---|---|
|
Lower-density pallet |
Lower lb/ft³ |
Higher class |
|
Denser pallet |
Higher lb/ft³ |
Lower class |
This is why the density calculation needs to be accurate. If the density is wrong, the pallet may be matched to the wrong range on the freight class chart.
How Does Inaccurate Density Affect Freight Classification?
If the pallet dimensions are wrong, the density will be wrong too. If that new density falls into a different range on the freight class chart, the freight class changes.
Take the same 500 lb mixed pallet from the earlier example. At 48 × 40 × 48 inches, its density is 9.4 lb/ft³, which puts it at Class 100.
If the height is entered as 60 inches instead of 48, the pallet looks taller in the calculation. That makes the pallet look like it takes up more space than it really does. The calculated density comes to about 7.5 lb/ft³, which puts it at Class 125.
The pallet itself has not changed. Only the recorded height has. But that one wrong dimension changes the density and moves the pallet from Class 100 to Class 125.
Why Do Accurate Pallet Dimensions are Important for the Freight Class Chart?
For a mixed pallet classified by density, the dimensions used in the calculation need to match the pallet as it is shipped. If the pallet dimensions are off, the cube is off too, which changes the density used to find the freight class.
For palletized freight, NMFTA bases cubage on the greatest straight-line length, width, and height of the handling unit as it is presented for shipment. That includes any overhang or part of the load that extends beyond the pallet.
This is where pallet dimensioning helps. vMeasure Pallet Ultima captures the pallet’s length, width, and height, along with shipment images. The dimensional data can then be sent to systems such as a WMS, TMS, or shipping software through no-code API integrations.