How freight class is set
The National Motor Freight Classification (NMFC) groups LTL freight into 18 classes from 50 (dense, cheap to ship) to 500 (light and bulky). For most freight, density — pounds per cubic foot — is the primary driver, which is why the same product ships cheaper when it's packed denser and palletized tightly. Measure the handling unit as it actually ships, including the pallet and any overhang, and divide total weight by total cubic volume.
The NMFC density guideline
| Density (lb/ft³) | Class |
|---|---|
| Less than 1 | 500 |
| 1–2 | 400 |
| 2–3 | 300 |
| 3–4 | 250 |
| 4–5 | 200 |
| 5–6 | 175 |
| 6–7 | 150 |
| 7–8 | 125 |
| 8–9 | 110 |
| 9–10.5 | 100 |
| 10.5–12 | 92.5 |
| 12–13.5 | 85 |
| 13.5–15 | 77.5 |
| 15–22.5 | 70 |
| 22.5–30 | 65 |
| 30–35 | 60 |
| 35–50 | 55 |
| 50 or more | 50 |
Denser freight rates cheaper. To ship denser, improve how cases fill a pallet — try the pallet calculator — and right-size cartons to cut the air you pay for.
Questions
How is freight class calculated?
For most freight, class is driven by density: total weight divided by total cubic volume, in pounds per cubic foot. That density maps to one of 18 NMFC classes from 50 to 500. Commodity, stowability, handling, and liability can also affect the governing class.
What is a good freight class?
Lower classes cost less to ship. A dense, sturdy, stackable pallet lands in a low class like 50 to 70; a light, bulky, or fragile shipment lands in a high class like 250 to 500. Packing denser and palletizing tightly lowers your class.
Is this calculator's class guaranteed?
No. It is a density-based estimate from the standard guideline. The actual NMFC classification can depend on the commodity and other factors, and some items have a fixed class. Confirm with the NMFC or your carrier before you tender the shipment.
Should I include the pallet in the measurement?
Yes. Measure and weigh the handling unit exactly as it ships — product, packaging, and pallet, including any overhang — because that is what the carrier measures.
Ship a lower class by design.
PackOS estimates density, case pack, and pallet build as you spec — so freight class is something you engineer, not discover on the invoice.