Freight class is based on the density, stowability, handling, and liability of your shipment. Using our freight class calculator, you can enter the weight and dimensions of each piece to get an estimated class instantly. For official NMFC codes and classification rules, visit the NMFTA.

In addition to density, freight class also depends on:

• Stowability: How easily it fits with other freight.

• Handling: Whether special care or equipment is required.

• Liability: The risk of damage, theft, or spoilage.

These criteria are defined by the National Motor Freight Classification® (NMFC).

Yes. Whether you’re shipping cartons, crates, pallets, or other packaging types, our calculator works for all. Simply enter the dimensions and weight for each unit, and the system will determine total density and estimated freight class.

The standard formula is:
Density = Weight (lbs) ÷ Volume (cubic feet)
Where volume is:
Length × Width × Height (inches) ÷ 1,728

Our freight class calculator does the math for you, saving time and helping prevent costly misclassifications.

To determine the cubic dimensions of a shipment, measure the length, width and height. Next, multiply the length by the width by the height to obtain the cubic dimensions in inches.

Length 24″, width 18″, height 18″
24″ x 18″ x 18″ = 7,776 cubic inches

To convert cubic inches to cubic feet, divide cubic inches by 1,728 (the number of cubic inches in a cubic foot).

7,776 % 1,728 = 4.5 cubic feet

To determine the density, divide the weight of the shipment (80 pounds) by the number of cubic feet.

80 % 4.5 = 17.78 pounds per cubic foot

To determine the dimensional weight, divide cubic inches by 194 (the dimensional factor).

7,776 % 197 = 40.08 dimensional pounds

In cases where the shipment is palletized, the dimensions of the pallet determine cubic dimensions. Although the original dimensions of the carton remain the same, the cubic dimensions now include the pallet.

Length 48″, width 40″, height 24″ (carton height of 18″ plus pallet height of 6″)
48″ x 40″ x 24″ = 46,080 cubic inches

Convert to feet by dividing by 1,728

46,080 % 1,728 = 26.7 cubic feet

The density then equals the weight, 110 pounds (80 lbs for the carton and approximately 30 lbs for the pallet), divided by the number of cubic feet.

110 % 26.7 = 4.12 pounds per cubic foot
80lb. Carton + 30 lb. Carton = 110 lb. Total

Our calculator provides an estimated freight class based on density. If you need to verify an official NMFC code or classification, use the NMFTA's official ClassIT lookup tool (login required). For most shipments, our calculator gives a reliable class reference to share with your carrier or broker.

Freight class directly affects your LTL rate. Lower classes (more dense, easier to handle) are cheaper to ship. Higher classes cost more due to space, fragility, or special handling requirements. Knowing your estimated class in advance helps you budget accurately and avoid unexpected fees.

Absolutely. Repackaging loose boxes into a shrink-wrapped pallet can increase density, improve handling, and reduce your freight class. This is one of the most overlooked ways to cut LTL shipping costs. Our calculator reflects these changes instantly when you update your shipment dimensions.

No — it is an estimated class based on density only. Official freight class assignments are governed by the NMFC and may require a subscription or carrier verification. However, our tool is highly accurate for most general freight and can be used as a strong reference when booking LTL shipments.