NMFC · 13 subprovision density scale

Freight class calculator

Put the right class on the bill of lading before reweighs start.

Enter each pallet's size and weight to get its density in pounds per cubic foot and the class on the NMFTA 13 subprovision scale.

Last updated 2026-09-27. Math runs in your browser, no data leaves your computer.

Measure the pallet exactly as it will leave your dock, wrapped and with any overhang, because the carrier's dimensioner measures the same way. Density is worked out per handling unit, so enter one pallet at a time and the count of identical pallets.

Units

Measure from the floor to the highest point, pallet deck included, since two extra inches of height on a 48 by 40 pallet can drop the density into the next class.

Use the scale weight with pallet, wrap and corner boards, because the carrier reweighs the whole unit.

The class does not change with the count, and the tool uses it only for the shipment totals on the bill of lading.

Before the booking, screen the name on the invoice. Shipment pre-check is on the paid plans, from USD 59 a month.

General guidance only. Verify against the cited primary sources before you commit to a shipment, declaration, or contract.

The 13 subprovision density scale

Most LTL carriers price on NMFC class, and since July 19, 2025 more than 2,000 items take their class from density, according to NMFTA. A wrong class on the bill of lading is caught when the carrier measures and reweighs the pallet, and the invoice arrives rebilled at the class the carrier found.

The table below is the standard scale as printed under NMFC item 47500 in NMFTA Docket 2026-2, issued August 28, 2026, which calls it the FCDC's standard 13 subprovision density scale. Density is in pounds per cubic foot.

Sub Density (lb per ft³) Class
1 Less than 1 400
2 1 but less than 2 300
3 2 but less than 4 250
4 4 but less than 6 175
5 6 but less than 8 125
6 8 but less than 10 100
7 10 but less than 12 92.5
8 12 but less than 15 85
9 15 but less than 22.5 70
10 22.5 but less than 30 65
11 30 but less than 35 60
12 35 but less than 50 55
13 50 or greater 50

Density is weight in pounds divided by volume in cubic feet, where volume is length times width times height in inches divided by 1,728. Metric entries convert at 2.54 cm per inch and 0.45359237 kg per pound, the NIST SP 811 factors, and the result also shows kilograms per cubic meter at 16.01846 per lb per cubic foot.

Item 110 of the NMFC says that where a shipment has several handling units, density is calculated on each one, and the total weight over the total cube is used only when the shipping papers give no more than a total weight. Put each pallet's weight and size on the bill of lading so the carrier has no reason to fall back to the total.

Worked example. One tall pallet, one class too high

The booking. A distributor ships a 48 by 40 pallet of cartons stacked 60 inches high at 520 lb. The shipping clerk copies class 100 from last year's paperwork, and the carrier accepts the booking, which looks fine on paper.

The failure. The volume is 48 × 40 × 60 / 1,728 = 66.7 cubic feet, so the density is 520 / 66.7 = 7.8 lb per cubic foot. On the 13 subprovision scale that sits in Sub 5, class 125, and the carrier's dimensioner finds exactly that and rebills the shipment. The choice is the usual one: change the cargo, or change the packing.

The fix. The warehouse restacks the same 520 lb onto the pallet at 48 inches high, which the carton size allows. The volume drops to 48 × 40 × 48 / 1,728 = 53.3 cubic feet and the density rises to 9.75 lb per cubic foot, Sub 6, class 100. The pallet ships at the class on the bill of lading and nothing is rebilled.

Building the pallet in the first place? The pallet calculator works out boxes per layer and layers per pallet for a height limit you set, so you can test a lower stack before the order is packed.

Frequently asked

How is freight class calculated from density?

Divide the weight of the handling unit in pounds by its volume in cubic feet to get pounds per cubic foot, then read the class off the density scale your NMFC item points to. On the NMFTA standard 13 subprovision scale, 7.8 lb per cubic foot falls in Sub 5, "6 but less than 8", which is class 125.

What changed in the NMFC density scale in 2025?

NMFTA says the changes took effect on July 19, 2025. More than 2,000 items moved to density based classes, and the standard density scale went from 11 subprovisions to 13. The 13 subprovision scale runs from class 400 for under 1 lb per cubic foot to class 50 for 50 or more.

Does every product use this density scale?

Not every product does, because some NMFC items still carry a fixed class or their own scale, because handling, stowability or liability set the class rather than density. Look up the item for your product in NMFTA ClassIT+ or ask the carrier, and use this tool when that item points to the 13 subprovision scale.

Do I measure the pallet or the product?

Measure the handling unit as tendered, pallet included, at its longest, widest and tallest points. NMFTA notes that density uses the total weight and cubic feet of the shipment or handling unit, and that measurements take in pallets and packaging. Overhang counts, so a carton sticking out past the deck edge sets the length.

What if I ship several pallets that are not identical?

NMFC Item 110 says density is calculated on each handling unit where the shipment has more than one. Run each different pallet through the tool separately and put each weight and size on the bill of lading, because carriers fall back to the total weight and total cube only when the paperwork gives nothing else.

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