15 - 22.5 pcf · NMFC density scale
The rating for freight at 15 - 22.5 pounds per cubic foot on the current 13-band NMFC density scale. Typically machined parts, small appliances, paint.
Class 70 is the single most-searched class number, and for good reason: the 15 - 22.5 pcf band is where a huge share of general industrial freight lands. Machined parts, small appliances, engines and paint all commonly rate here. Watch the lower edge: 15.00 pcf exactly is class 70, but 14.99 pcf drops you to class 85 and a higher rate.
Worked example. A standard pallet: 48 × 40 × 48 in, 960 lb. That is 53.3 cu ft and 960 lb → 18.00 pcf → class 70. Run your own numbers →
Band edges are inclusive at the bottom, exclusive at the top: exactly 15 pcf is class 70, but just below it the class gets more expensive — 14.99 pcf rates class 85. A few pounds of packaging or an inch of pallet height can move a borderline shipment across that line.
Freight class runs from 50 (densest, cheapest per pound) to 400 on the current density scale. Class 70 is band 5 of 13.
Either side of this band: denser freight (22.5 - 30 pcf) rates class 65, which is cheaper; lighter freight (12 - 15 pcf) rates class 85, which costs more.
The full table is on the freight class chart, and the calculator works out density and class from your dimensions, including multi-pallet shipments.