What is freight class 400?

Freight class 400 is the NMFC rating for freight with a density of under 1 pounds per cubic foot under the current density scale (Docket 2025-1, effective July 2025). Typical examples: bagged insulation and other extremely light freight.

What density is class 400?

Class 400 covers under 1 lb per cubic foot. Bands are inclusive at the lower edge and exclusive at the upper edge.

Is class 400 expensive to ship?

Lower classes are cheaper per pound. Class 400 is position 13 of 13 on the current scale, so it prices toward the expensive, light end of LTL freight.

Freight Class 400: Density Range, Typical Freight & Cost Position

What ships at class 400

Class 400 is the top of the current density scale, for freight under 1 pcf. Class 500 is not on the scale at all, though an older density guideline mapped sub-1 pcf freight to it - which is why some free calculators still return 500 for very light freight. We tested that: see the calculator audit.

Worked example. A standard pallet: 48 × 40 × 48 in, 40 lb. That is 53.3 cu ft and 40 lb → 0.75 pcf → class 400. Open this example in the calculator →

Where the edges are. On that same 48 × 40 × 48 in pallet (53.3 cu ft), class 400 covers every weight from 1 lb up to 53 lb; at 54 lb it rates class 300. Enter your own shipment in the calculator and it tells you how far you are from either edge.

Freight in this band is also where an out-of-date calculator hands you class 500. That number is not on the current density scale, so seeing one back from a density calculation means the tool is reading an older guideline.

Where class 400 sits on the scale

Freight class runs from 50 (densest, cheapest per pound) to 400 on the current density scale. Class 400 is band 13 of 13.

Either side of this band: denser freight (1 - 2 pcf) rates class 300, which is cheaper.

The full table is on the freight class chart, and the calculator works out density and class from your dimensions, including multi-pallet shipments.

Density is the default, not the whole rule. Since Docket 2025-1 most commodities class by density, but items with unusual stowability, handling or liability characteristics can class differently. Confirm the NMFC item before the BOL goes out.