Freight Class Chart (NMFC Density Scale): All 13 Classes Explained

In United States LTL (less-than-truckload) shipping, every rate quotation begins with one value: the shipment's freight class, a number from 50 to 500 assigned under the NMFC (National Motor Freight Classification). The scale runs inverse to density — denser, more compact freight carries a lower class and a lower rate per hundredweight. The reference table below is the map: it pairs density in pounds per cubic foot (pcf) with each of the 13 density-based classes, so you can place a shipment yourself before the carrier assigns it.

Under the NMFC's 2025 overhaul (Docket 2025-1, effective July 2025), most commodities are now rated by density alone on a standard 13-tier scale. The practical effect is that classification became a calculation rather than a commodity-by-commodity lookup: the class follows directly from dimensions and weight.

The Freight Class Chart: All 13 Density Tiers

Read each band as closed at its lower bound and open at its upper: exactly 15 lb/ft³ resolves to class 70, exactly 12 to class 85. Placing a shipment requires a single derived figure — density = total weight (lb) ÷ total volume (ft³), where ft³ = (L in × W in × H in × pieces) ÷ 1,728. The full procedure, with the errors it is easy to make, is documented in how to calculate freight density; the freight class calculator returns the class directly.

Reading the Staircase

Plotted, the table is a staircase: class descends as density climbs, but the treads are unequal. Below 15 pcf the bands are narrow — one or two pcf wide — while above 15 pcf they broaden. That asymmetry is where the cost concentrates: low-density freight sits on the steep part of the curve, where a small measurement change crosses a band, and crossing a band changes the rate.

Trace it left to right: under 1 pcf the shipment falls in class 400 (styrofoam, empty drums); the staircase then drops steeply through the parcel-like middle bands; and from 15 pcf onward the treads lengthen, so dense industrial freight settles into classes 70 and below.

Four Shipments, Placed on the Table

Note the fourth row against the first: the lampshades weigh a fifth of the books yet rate in a far costlier class, because in LTL density sets the class, not weight. Each row opens in the calculator with its dimensions pre-filled — the book pallet lands at exactly 22.5 pcf, the class 65 boundary, and the lampshade pallet demonstrates how a light, bulky unit drops to class 250. Adjust the figures to place your own freight.

What Changed in the 2025 NMFC Revision

• Standard density scale. Most commodities that formerly held fixed classes were moved onto the 13-sub density scale above. The older 18-class ladder (retaining 77.5, 110, 150, 500) still exists in the NMFC, but density-rated freight now resolves through the 13 tiers.

• New high-density subs. The bands at 30–35, 35–50, and 50+ lb/ft³ — classes 60, 55, and 50 — were formalized, so very dense freight now lands in its proper low-cost classes.

• Exceptions preserved. Hazmat, machinery with attachments, fragile goods, and unusually long articles keep their commodity-specific classes or modifiers. Density is the default rule, not the universal one; where it is uncertain, consult the NMFC item or the carrier.

The governing authority is the

, which publishes the NMFC and maintains ClassIT, its online lookup tool. A chart such as this one is a working aid; where the two disagree, the NMFC item controls.

How Class Reaches the Rate

LTL base rates are quoted per 100 lb (CWT) per class. A shift from class 70 to class 125 raises the base rate roughly 40–80% on the same lane, and further on some tariffs. Benchmark tariffs such as SMC³ CzarLite, and each carrier's own rules tariff, set the exact multipliers, but the direction is constant. Three consequences follow directly from the table:

1. Palletize tight and low. Void air inside the pallet lowers density and can push the shipment up a class. A 60-inch pallet carrying 12 inches of headspace is a self-inflicted rate increase; carton layout is the correction (see how many boxes fit on a pallet).

2. Density near a break rewards engineering. At 11.8 lb/ft³ the shipment is class 92.5; compressing packaging to 12.0 moves it to class 85. On a repeated lane, a small packaging change compounds.

3. Declare accurately. Carriers reweigh and re-cube as a matter of routine. An inspection that reclassifies a 92.5 shipment to 175 costs more than the accurate quote would have.

Anatomy of a Reclassification

The gap between product math and pallet math is where a corrected invoice originates. Take a machine-shop shipper quoting a pallet of steel brackets: the cartons alone measure 15.2 pcf, so the bill of lading reads class 70. At the origin terminal a dimensioner scans the handling unit — pallet deck, two inches of overhang per side, a domed stretch-wrap crown — and reads 7.8 pcf. That is the 6–8 band, class 125.

The effects compound. The base rate rises roughly 40–80% across the 70-to-125 jump, more on some tariffs. A weigh-and-inspection (W&I) fee from the carrier's rules tariff is applied per occurrence. And because the shipper's negotiated discount was written against the declared class, the corrected line items rate less favorably than anything the shipper had ever quoted. None of it is a penalty in the legal sense; it is the price of the freight as measured. Prevention is free: measure the finished pallet at its extremes, compute the density, and quote the class the dimensioner will read. The measuring procedure is set out in how to calculate freight density.

Where the Density Table Stops Governing

• Commodity exceptions. Certain NMFC items assign a class irrespective of density — typically freight carrying liability, stowability, or handling problems (hazardous materials, live plants, very long or fragile articles). Where a commodity has its own NMFC item, that item overrides the density table.

• Exact boundaries. Bands take their lower bound, and carriers round dimensions up to the next inch. Freight that calculates to 12.05 pcf can measure 11.9 at the dock once the height gains an inch of wrap. Treat any density within a few percent of a break as the lower band until real margin has been engineered.

• Non-standard handling units. Drums, bundles of pipe or lumber, and articles longer than roughly 8 feet can invoke linear-foot rules or overlength charges that rate the shipment outside plain class math. Pallet footprint standards bear on this as well — see standard pallet sizes.

• FAK agreements. High-volume shippers frequently negotiate freight-all-kinds (FAK) rates that collapse a range of classes into one rating class. A FAK alters what is paid, not what the freight is; reclassification can still void the FAK terms where declarations are habitually wrong.