Freight Class Calculator

Freight class is a standardized classification system (NMFC) used by LTL carriers to price shipments. It ranges from Class 50 (lowest cost, highest density) to Class 500 (highest cost, lowest density). Using the wrong freight class when booking a shipment can result in carrier reclassification fees of $50-$150+ per incident, plus shipment delays.

Under the 2025 NMFC system, freight class is primarily determined by density -- your shipment's weight divided by its volume (measured in pounds per cubic foot, or PCF). Higher density = lower class number = lower shipping cost. The calculator takes your dimensions and weight, computes the density, and maps it to the correct class on the NMFC density scale.

In July 2025, the NMFTA overhauled the freight classification system, reclassifying nearly 100 commodity groups to a density-based structure. Many products that previously had fixed class assignments are now classified by density. This means accurate density calculation is more important than ever. Our calculator uses the updated 2025 density-based scale.

Reclassification happens when a carrier re-measures your shipment and determines it belongs in a different (usually more expensive) freight class. Our tool calculates how close your density is to a class boundary. If your density is within 5-10% of a boundary, you get a warning -- this is the danger zone where carriers are most likely to bump you to a higher class.

Yes! Batch mode lets you calculate freight class for up to 100 items at once. Enter dimensions and weight as tab or comma-separated values (one item per line), or upload a CSV/Excel file. All results can be exported to CSV.

While density is the primary factor, carriers may also consider stowability (can it be stored efficiently?), handling (does it require special care?), and liability (is it high-value or perishable?). These factors can cause a carrier to assign a higher class than density alone suggests. Our tool provides advisory prompts about these factors after calculation.

Yes. You can enter dimensions in centimeters and weight in kilograms. The calculator automatically converts to imperial units for the density calculation (since NMFC uses pounds per cubic foot) and displays results in your chosen unit system.

The 14-day free trial gives you full access: single and batch mode, CSV export, reclassification risk warnings, beyond-density advisory, and calculation history. Trial users get 5 uses per day with up to 10 items per use. No credit card required. Subscribers get unlimited uses and items.