Freight Class 400
Class 400 is the top of the current NMFC density scale: freight under 1 lb/ft³ that occupies a lot of space for very little weight.
What is class 400 freight?
Since July 19, 2025, class 400 is the top of the NMFC density scale. It covers any density-rated freight that weighs less than 1 pound per cubic foot, such as loose foam packaging, boxed lampshades and inflatables. Class 500 still exists, but only through specific commodity listings. A 48 × 40 × 48 in pallet (53.3 ft³) that weighs under about 53 lb is class 400.
Class 400 is now the top of the density scale
Since July 19, 2025, class 400 covers all density-rated freight under 1 lb/ft³. NMFC Docket 2025-1 replaced the old 18-row table with a 13-tier scale. Class 500 lost its density band and now applies only through specific commodity listings, so anything lighter than 1 lb/ft³ rates 400 unless its listing says otherwise. The old class 400 range, 1 to 2 lb/ft³, now rates class 300.
Freight this light is closer to packaging than cargo: loose foam, lampshades, antlers, inflatables — awkward shapes whose cartons protect a silhouette rather than hold a mass. A trailer packed full of it can gross less than three pallets of class-50 fasteners. The carrier is selling you almost pure volume, and the rate reflects it.
Class 400 worked examples
Three shipments measured at their outside size. The last one shows how nesting the product moves it down.
Large lampshades, loosely boxed — class 400
A carton of lampshades, 36" × 36" × 48", 32 lb.
36 × 36 × 48 = 62,208 in³ ÷ 1,728 = 36.0 ft³. Density = 32 lb ÷ 36.0 ft³.
0.9 lb/ft³ → under 1 → class 400 on the current NMFC scale (the pre-2025 table said 500).
Unassembled furniture frames — now class 300
Light frame kits stacked 70" high on a 48" × 40" pallet, 120 lb.
48 × 40 × 70 = 134,400 in³ ÷ 1,728 = 77.8 ft³. Density = 120 lb ÷ 77.8 ft³.
1.5 lb/ft³ → class 300 on the current scale. Under the pre-2025 table this was class 400.
The same shades, nested — class 300
The identical 32 lb of shades nested into a 36" × 36" × 24" carton.
36 × 36 × 24 = 31,104 in³ ÷ 1,728 = 18.0 ft³. Density = 32 lb ÷ 18.0 ft³ = 1.8 lb/ft³.
1.8 lb/ft³ → class 300. Half the carton height moved it off the top of the scale.
Escaping the top of the scale
Most freight under 1 lb/ft³ got there through a packing choice: shapes shipped assembled, shells shipped un-nested, cartons sized for the largest variant and filled with void. Nest aggressively. Tapered and hollow shapes such as shades, buckets and cones are made for it. Crossing 1 lb/ft³ reaches class 300, and crossing 2 reaches class 250, a band that now runs up to 4 lb/ft³.
Where nesting can't help, question the assembled state (frames ship as sticks, not rectangles) and the carton spec (one right-sized carton per variant beats one huge carton for all). Compression works on soft goods: vacuum-bagged foam recovers its shape on arrival. Rigid cartons and honest, tight dimensions also stop a bowed carton wall from adding measured cube at the dock.
What ships as class 400
Very light goods that often measure under 1 lb/ft³. A specific NMFC listing can set a different class:
- Deer antlers
- Loosely boxed lampshades
- Uncompressed foam packaging
- Inflatable goods
Is your shipment class 400?
Enter the size and weight as shipped. Anything under 1 lb/ft³ is class 400; from 1 up it is class 300.
Density-based estimate. Some commodities carry a fixed NMFC class — check our freight class by commodity pages.
Estimated Freight Class
Density
0.51
lb/ft³
Volume
53.33
ft³
Weight
27
lb
0–1 lb/ft³ → Class 400
NMFC density scale (Docket 2025-1, effective July 19, 2025)
Pre-July-2025 table: class 500. Use it only if your carrier contract still prices on the old table.
Free PDF includes a watermark. Pro removes it & adds your brand.
Estimates only — verify freight class/NMFC and chargeable weight with your carrier.
Uses the 13-tier NMFC density scale (Docket 2025-1). See the full freight class chart.
Frequently asked questions
What is class 400 freight?
Density-rated freight under 1 lb/ft³, such as loose foam, boxed lampshades and inflatables. Since the 2025 NMFC change it is the highest class on the density scale.
What density is freight class 400?
Under 1 pound per cubic foot on the current NMFC scale (Docket 2025-1, effective July 19, 2025), measured on the shipped unit at its extreme points. At 1 or above the shipment drops to class 300. Under the older table class 400 was 1 to under 2, and freight under 1 was class 500.
Is class 400 the highest freight class now?
It is the highest class on the density scale. Class 500 still exists, but only through specific NMFC commodity listings, usually for goods with extreme value or liability per pound. Density-rated freight never goes above 400 on the current scale.
How do I avoid class 400?
Change the shipment's shape, not the carrier: nest hollow items, ship frames knocked down, compress soft goods, right-size cartons per variant. Crossing 1 lb/ft³ reaches class 300, and 2 lb/ft³ reaches class 250.