There are eighteen classes in the classification and thirteen rungs on the density scale carriers publish. The gap between those two figures is the most useful thing on this page, because five classes exist that no density calculation will ever hand you.
The density scale runs through most of the ladder, and steps over five rungs entirely.
FedEx Freight states on its freight class calculator page, read 2026-07-28, that there are 18 classes numbered 50 to 500. Thirteen of them are rungs on the density scale that FedEx Freight and Estes both publish; the other five are not on that scale at all.
| Class | On the density scale | Density band, lb per cubic foot |
|---|---|---|
| 50 | Yes | 50 or greater |
| 55 | Yes | 35 but less than 50 |
| 60 | Yes | 30 but less than 35 |
| 65 | Yes | 22.5 but less than 30 |
| 70 | Yes | 15 but less than 22.5 |
| 77.5 | No | Item number only |
| 85 | Yes | 12 but less than 15 |
| 92.5 | Yes | 10 but less than 12 |
| 100 | Yes | 8 but less than 10 |
| 110 | No | Item number only |
| 125 | Yes | 6 but less than 8 |
| 150 | No | Item number only |
| 175 | Yes | 4 but less than 6 |
| 200 | No | Item number only |
| 250 | Yes | 2 but less than 4 |
| 300 | Yes | 1 but less than 2 |
| 400 | Yes | Less than 1 |
| 500 | No | Item number only |
Read the middle column and the shape of LTL pricing appears. Thirteen classes are arithmetic anyone can do on a dock. Five of them, 77.5 and 110 and 150 and 200 and 500, are decisions the classification made about a particular commodity, and the only route onto one of those rungs is the item number that carries it.
It maps density to class and stops there. It does not know that your commodity has its own item number, that the carrier will remeasure the wrapped load at a terminal, or that the wording on the document can move the answer. Use it to sanity check a class somebody quoted you.
Between class 92.5 and class 100 lies a density gap of two pounds per cubic foot. Between class 250 and class 300 the gap is one. Close to a boundary, a hundred pounds of packaging decides more than a hundred miles of lane.
The top of the ladder describes freight that is paying for space rather than weight. That is the region where pallet height, crating decisions and how tightly a load is wrapped start to outrank the goods themselves.
The classification is common across LTL carriers. The money is not: each carrier files its own rates against these classes and its own exceptions in its rules tariff, so the same class produces two different numbers at two carriers on the same day.
A class on its own prices nothing. It joins the lane, the weight bracket, the fuel line and every accessorial either end asks for, and a person assembles those against a carrier tariff. We sell US domestic parcel labels directly and route palletized freight to that person.
Work out a class from dimensions See where the class lands on a quote Hand the shipment to a person
FedEx Freight states on its class calculator page that there are 18 classes numbered 50 to 500. Thirteen of them sit on the density scale carriers publish, and five are reached only through a commodity item number.
Classes 77.5, 110, 150, 200 and 500. The published density scale runs through the other thirteen, so a shipment lands on one of these five because the classification assigns that class to the commodity itself.
Class 50, which the density scale reaches at 50 pounds per cubic foot or greater. It is the cheapest rung because that freight uses the least trailer space for its weight.
The classification behind it is common to LTL carriers, but each files its own rates against those classes and its own exceptions in its rules tariff, so one class does not produce one price across the market.