Freight Class Calculator (NMFC 2025 Density Scale)

By Owen Hartley, Editor · Last updated November 11, 2026

Enter each handling unit's dimensions and weight. The calculator returns cubic feet, density in pounds per cubic foot, the class on the 13-tier NMFC density scale in effect since July 19, 2025, and the class the same freight had on the old 11-tier scale.

How freight class is calculated from density

Multiply length, width and height in inches and divide by 1,728 to get cubic feet. Divide the weight in pounds by that number to get density in pounds per cubic foot (pcf). The density bracket on the scale below sets the class, from class 400 for the lightest freight to class 50 for the densest.

NMFTA uses this worked example in its 2025 FAQ: a pallet of boxes measuring 48 × 40 × 45 inches and weighing 450 pounds is 86,400 cubic inches, or 50 cubic feet. 450 ÷ 50 = 9.00 pcf, which falls in the 8-but-less-than-10 bracket: class 100.

The 13 density subprovisions this calculator uses

The calculator classifies freight on the standard 13-subprovision density scale that NMFC Docket 2025-1 put in place on July 19, 2025. Every bracket below is copied from NMFTA's own published table and checked against the same table in a FedEx Freight customer flyer. Each bracket includes its lower bound and excludes its upper bound.

Source: NMFTA, Decoding Density: The Freight Factor You Can't Afford to Overlook (blog, posted June 19, 2025); FedEx Freight, Understanding the upcoming NMFC classification changes beginning July 2025 (flyer, 05/25), checked Oct 30, 2026

• Sub 11: Narrowed by Docket 2025-1; before July 19, 2025 this sub read "30 or greater". Also stated in NMFTA's 2025 NMFC Changes FAQ.
• Sub 12, Sub 13: Added by Docket 2025-1. Also stated in NMFTA's 2025 NMFC Changes FAQ.

Read each range literally. "15 but less than 22.5" means a unit at exactly 15.00 pcf is class 70, while a unit at 14.99 pcf is class 85. The calculator keeps full precision when it picks the bracket, so a density that displays as 15.00 but is really 14.996 still lands in class 85; when that happens the result shows three decimals so you can see why.

How to measure a handling unit for density

NMFTA's FAQ describes the measurement: take the greatest straight-line length, width and height in inches, including the pallet and anything that sticks out, as the unit is tendered. Divide the product by 1,728. Use the weight of the whole unit as tendered, pallet and packaging included. Rounding generously or leaving out pallet height changes the answer.

When a shipment has several handling units, the NMFC rule NMFTA quotes (Item 110, Sec. 8(d)) says density is figured for each handling unit. If the shipping papers show only one total weight for all units, density may be figured from total weight and total cube. The calculator shows both: a class for each line you enter and the density of the whole shipment.

Why a carrier may bill a different class

The density scale applies only to items NMFTA classifies on full density, with no handling, stowability or liability concerns. Items flagged for those concerns keep classes set by their own characteristics. NMFTA also describes the NMFC as a voluntary standard, so a carrier's own tariff or your contract terms can override it.

Three more things this calculator cannot see:

• The NMFC item for your product. Looking up items is NMFTA's licensed ClassIT+ service; this site does not publish item numbers or descriptions.
• Mixed pallets. The NMFC rule for shipments of several different articles, Item 640, is being rewritten. NMFTA scheduled Docket 2026-3, which carries the new text, for release on November 6, 2026, with an effective date of January 23, 2027. Until then, the per-line classes here are a density check, not a ruling on how a mixed pallet will be billed.
• Freight-all-kinds (FAK) agreements. NMFTA notes that FAK terms are not part of the NMFC and are set between you and the carrier.

Same shipment, old scale vs new scale

Below 30 pcf the 2025 scale gives exactly the same class as the old 11-tier scale. The difference is only at the dense end: 30 to under 35 pcf stays class 60, 35 to under 50 pcf drops from class 60 to class 55, and 50 pcf or more drops from class 60 to class 50.

The "Before July 19, 2025" column in the result shows the old class so you can compare a quote or an old bill of lading. For the full side-by-side chart and the pallet weights that reach each class, see the freight class chart.

What "weight to the next class" means

For each line, the calculator also shows how many pounds you would have to add at the same dimensions to reach the lower edge of the next denser bracket. A 48 × 40 × 48-inch pallet at 500 pounds is 9.38 pcf, class 100; at 533.33 pounds it reaches 10 pcf and class 92.5.

The same logic works in reverse: cutting pallet height raises density without changing weight. The figure is arithmetic on your numbers, not a suggestion to add weight. It shows how close a unit sits to a class break, which is the point where a small measuring error can change the bill.

How the density math is done

Conversions use 1 inch = 2.54 cm and 1 pound = 0.45359237 kg exactly. Cubic feet are length × width × height in inches ÷ 1,728, multiplied by quantity. Density is total weight ÷ total cubic feet. Displayed values are rounded to two decimals; the bracket is chosen from the unrounded density.

Fifteen test cases, including the NMFTA worked example and an exact value at every bracket edge that changed, run on every build. If any result drifts, the page is not published. The scale itself is read from the same data file shown in the table above, so the calculator and the table cannot disagree.