Freight Class Calculator
Density decides the class. Get it right before you quote.
Enter dimensions and weight to get cubic feet, density in pounds per cubic foot, linear feet and the density-based NMFC freight class. No signup — and it runs the same logic our own rating engine uses, so the answer here is the answer your carrier will arrive at.
How freight class is calculated from density
Density is weight divided by volume. Take length × width × height in inches, divide by 1,728 to get cubic feet per piece, multiply by the number of pieces, then divide the total weight by that. The result is pounds per cubic foot, and it maps onto the NMFC density scale below.
| Sub | Density (lb per cubic ft) | Class |
|---|---|---|
| 1 | Less than 1 | 400 |
| 2 | 1 but less than 2 | 300 |
| 3 | 2 but less than 4 | 250 |
| 4 | 4 but less than 6 | 175 |
| 5 | 6 but less than 8 | 125 |
| 6 | 8 but less than 10 | 100 |
| 7 | 10 but less than 12 | 92.5 |
| 8 | 12 but less than 15 | 85 |
| 9 | 15 but less than 22.5 | 70 |
| 10 | 22.5 but less than 30 | 65 |
| 11 | 30 but less than 35 | 60 |
| 12 | 35 but less than 50 | 55 |
| 13 | 50 or greater | 50 |
This scale applies to density-based freight with no special handling, stowability or liability considerations. If you were expecting to see class 77.5, 110, 150, 200 or 500 — those exist in the NMFC, but they are assigned on commodity, handling, stowability or liability rather than on density, so no density calculator can produce them.
Why the class you calculate still gets changed
A correct density is necessary and not sufficient. These are the four things that reprice a load after it has already moved.
The dimensions were the pallet, not the freight
Carriers measure what leaves the dock — including the pallet, the shrink wrap, and anything overhanging. Measure what actually ships, not what is on the packing list.
The commodity outranks the density
Plenty of NMFC items carry a fixed class regardless of how dense they are. If the item has its own NMFC number, that number wins over anything this calculator says.
Linear feet, not class, was the problem
Long, light freight can price correctly by class and still trigger a linear-foot or cubic capacity rule that forces a volume quote. Density does not protect you from that.
Nobody checked until the carrier did
Every terminal runs freight across a certified scale and, increasingly, a dimensioner. A reweigh caught in transit is a correction; the same one found at settlement is a dispute.
This calculator gives you the number. Catching it on every load, automatically, before the quote leaves is what the rating engine and Live Audit do.
See it on your own freightMore on class and reweighs
What happens after the number is wrong, and how to argue it.
Nobody Checks the Freight Class Until the Carrier Does
There are a hundred guides on calculating freight class. Almost none address the real problem: the class you were given is inherited, and nobody has checked it in years.
Sep 2025LTL for BrokersHow to Win a Reweigh or Reclass Dispute (and Why Most Are Lost Before They Start)
Most reweigh disputes are lost weeks before anyone argues them — at the bill of lading. What the carrier has, what you have, and what actually wins.
Dec 2025LTL for BrokersThe LTL Accessorials That Show Up After You've Already Quoted
The accessorial that wrecks a quote is never the one somebody mentioned. It's the one the address implied and nobody asked about.
Oct 2025Getting reclassed anyway?
Send us a load that came back reclassed or reweighed and we will show you what was different between what you declared and what the carrier measured.