Freight that weighs 50 pounds per cubic foot or more now rates Class 50, and anything from 35 to under 50 lands one step higher at Class 55. Both tiers joined the density scale in July 2025, when the table grew from 11 tiers to 13.
Those tiers reward dense freight. They only pay off when your bill of lading matches what the carrier finds at the dock. Terminals run pallets through dimensioners that capture dimensions and weight. A two-inch miss on height can push a load across a class break. The carrier then reclassifies the shipment and bills you the difference.
Freight density drives that whole chain. Measure it correctly, and the freight class on your paperwork holds from pickup to invoice. Measure it loosely, and every load carries a quiet surcharge. The sections below walk through the math for pallets, mixed loads, and freight that won’t sit square.
How Freight Density Shapes Your LTL Classification
Density now decides more classes than any other factor. The National Motor Freight Traffic Association (NMFTA) moved a large share of commodities onto one density table in 2025, and later dockets kept that shift going. The commodity name on your paperwork still matters, but the math carries more of the outcome. Our earlier guide to National Motor Freight Classification (NMFC) codes and the density chart covers lookup tools in depth. This section focuses on how the breaks behave.
Here is how the 13 density bands line up with their classes:
| Density (PCF) | Class | Density (PCF) | Class |
| Less than 1 | 400 | 12 to under 15 | 85 |
| 1 to under 2 | 300 | 15 to under 22.5 | 70 |
| 2 to under 4 | 250 | 22.5 to under 30 | 65 |
| 4 to under 6 | 175 | 30 to under 35 | 60 |
| 6 to under 8 | 125 | 35 to under 50 | 55 |
| 8 to under 10 | 100 | 50 or greater | 50 |
| 10 to under 12 | 92.5 | ||
Higher density earns a lower class. Lower density pushes a shipment toward Class 400. The bands also narrow at the light end, so a fraction of a pound can change an LTL classification there.
Not every item follows this table. The classification marks items with handling, stowability, or liability concerns with a special symbol, and those keep classes that reflect more than density. Always confirm an item’s current treatment in ClassIT+ before you rate it.
Freight density gives you the starting class. The measurements you feed it decide whether that class holds.
How to Find Pounds per Cubic Foot for a Single Pallet
One pallet is the simplest load to rate. It’s also the most common source of LTL classification errors. The formula takes two inputs, weight and volume, and both drift easily from what the carrier records.
Work through these steps to calculate density for every pallet before you book:
- Measure the outer box. Record length, width, and height in inches at the widest points, rounding any fraction up. Include the pallet, the stretch wrap, and any overhang.
- Find the volume. Multiply the three measurements to get the number of cubic inches. Divide that figure by 1,728 to convert it into cubic feet.
- Weigh the full unit. Use the gross weight of the shipment, pallet included.
- Divide the weight by the volume. Match the result to its band in the table above.
One missed measurement shows the risk. A 48 x 40 pallet stands 50 inches tall and weighs 1,100 pounds. That works out to 19.8 pounds per cubic foot, which rates Class 70. Leave out the 6-inch pallet base, and that freight reads 22.5 on paper and rates Class 65. The carrier’s dimensioner records 50 inches, and the invoice comes back at Class 70.
Reclassification charges like that one surface later as freight invoice errors your team has to dispute. Clean numbers on one pallet set the standard for everything that follows. Mixed pallets add a second layer of rules.
Handling Mixed Pallets and Multi-Piece Shipments
Multi-piece LTL shipments raise a question one pallet never does. Does the carrier rate each unit, or the whole load? For shipments of separate handling units, Item 110 of the NMFC sets the approach. Mixed pallets carrying several commodities on one unit are a different matter; those fall under Item 640, which is still in flux.
Match your shipment to the scenario that fits:
- Several handling units, with each unit’s weight listed. Item 110 calls for density on each handling unit. Two pallets on one bill of lading can rate in two classes.
- Several handling units, with one combined weight listed. The carrier may divide the total weight by the shipment’s overall cube. The load then rates as one blended density, which can help or hurt depending on the mix.
- Mixed pallets carrying several commodities. Rule 640 governs these loads, and the rule has been under active review, so its treatment of mixed commodities can shift from one docket to the next. Check the current version of Rule 640 and confirm each carrier’s reading before you tender.
- Single-product units grouped on one bill of lading. Each unit follows its own density band, as long as each unit’s weight appears on the bill of lading. Packing one product type per pallet keeps your freight density math easy to defend.
Clear unit-level records make each class easier to prove. Teams that combine orders through freight consolidation should list the weight of each unit on the bill of lading. That habit keeps the LTL classification tied to how the freight actually rides. Odd shapes bring their own measuring problem.
Measuring Oversized Freight and Odd-Shaped Loads
Irregular freight breaks the box math behind every LTL classification. A load’s class reflects the space it occupies on the trailer, not its shape. Three situations cause most of the trouble.
Cylinders, Drums, and Irregular Items
A drum or a casting with curves leaves empty air around its edges. LTL carriers typically measure the rectangle the item fills at its longest, widest, and tallest points. That empty air counts as volume, so your freight density drops and the class rises. Crating or squaring off the load can recover some of that loss.
Overhang
Product that hangs past the pallet edge adds volume without adding weight. Two inches of overhang on each side can drag a pallet into a higher band. Overhanging cartons can also cause damage during transit. Keep cartons inside the pallet footprint.
Non-Stackable and Oversized Loads
Many carrier tariffs bill a non-stackable pallet as if it filled the trailer to the roof. Bulky shipments can also trigger a cubic capacity rule, which sets shipping rates by space rather than class. Mark stackability correctly on the bill of lading and check each tariff when you plan your shipment.
These rules shift by carrier, so consistent measuring has to become a team habit across standard pallets, mixed pallets, and oversized loads alike.
Supply Chain Solutions helps shippers build that habit, from measurement standards at the dock to carrier selection and invoice review. That way, your pounds per cubic foot figures hold up at billing.
Keep Your LTL Classification Accurate
A reclass notice rarely arrives alone. One missed inch on a pallet turns into a back charge, a dispute, and an hour your team never gets back. Multiply those charges across a month of mixed pallets and oversized loads, and the cost adds up fast. Most of them trace back to a tape measure, not a rate sheet.
Supply Chain Solutions works with operations teams to tighten freight classification from dock to invoice. We audit how your team measures and documents each load and route freight to carriers whose tariffs fit it. You keep the savings that well-measured freight should earn.
Talk to our freight team about the classes on your next bill of lading.
Frequently Asked Questions
What is freight density?
It measures how much a load weighs relative to the space it takes up. You find it by dividing the weight of your shipment by its volume in cubic feet. The result sets the starting point for your LTL freight class.
How do you work out freight density for a pallet?
Measure length, width, and height, including the pallet, to the inch. Multiply the three, then divide by 1,728 to get total cubic feet. Divide total pounds by that figure to determine the density. A density calculator tool speeds up the math, but only with accurate inputs.
Does density alone set a shipment’s freight class?
Not always. Classification rests on a review based on four characteristics: density, handling, stowability, and liability. Items that carry handling or liability flags can rate at a class density alone wouldn’t produce. Check your item’s listing in ClassIT+, especially for hazardous or irregularly shaped freight.
How many freight classes are there?
The system lists 18 classes, running from 50 to 500. The standard density table uses 13 of them, and each band points to one corresponding freight class. Classes 77.5, 110, 150, 200, and 500 sit outside those bands.
How does class affect the LTL rate you pay?
Each step up in class raises the charge per hundred pounds. Light freight uses too much space for the revenue its weight brings in. High-density items rate at the low end of the scale, which keeps freight shipping costs down.
Is an online freight class calculator reliable?
A calculator can help determine your band. Some calculators still run the old 11-tier scale, which stops at Class 60. They also can’t spot items with handling flags. Get an accurate density first, then confirm the class with your carrier.
How do you find the right freight class for mixed pallets?
Record weight and dimensions for each handling unit, and list them separately on the bill of lading. Item 110 rates density per unit when each unit’s weight appears. Determining freight class for several commodities on one pallet falls under Rule 640, so confirm the carrier’s approach first.
Why do carriers reclassify freight?
Many terminals run freight through dimensioners, and those readings can differ from your paperwork. A shipment density near a class break turns a small gap into a class change. The class reflected on the invoice then follows the carrier’s numbers. Photos, scale tickets, and measurement records support a dispute and help you avoid repeat charges.