Freight Class Calculator (Estimated Density-Based)
Calculate shipment density and estimate LTL freight class across the standard 13 density tiers.
Live Calculation Results
Estimated density-based freight class
11.25 lb/ft³ · 10 to <12 lb/ft³ band
- Density
- 11.25 lb/ft³180.21 kg/m³
- Total volume
- 106.667 ft³3.020 m³
- Total weight
- 1,200.00 lb544.31 kg
- Handling units
- 2
What this means
- At 11.25 lb/ft³, this freight falls in the 10 to <12 lb/ft³ band, which maps to class 92.5 in the density structure used here.
- The next lower-numbered class (85) starts at 12 lb/ft³. On the same volume that would need about 80 lb more total weight, or less volume at the same weight.
- The next higher-numbered class (100) applies below 10 lb/ft³.
- This is a density-based estimate, not an official NMFC commodity lookup. The class on your bill of lading depends on the NMFC item and any handling, stowability or liability rules.
Assumptions used
- Density = total weight ÷ total volume, using the outer dimensions you entered.
- Classes follow the 13-sub density structure (see the Freight Class Chart guide). Boundaries: lower value included, upper value excluded.
- Handling, stowability and liability characteristics are not evaluated.
Planning Notice & Scope Boundary
This is a density-based planning estimate, not an official NMFC commodity classification or carrier tariff guarantee.
Formula & Calculation Methodology
Density (PCF) = Total Gross Weight (lb) ÷ Total Shipment Volume (ft³). The resulting PCF maps to a freight class band.
Density = Weight (lb) / Volume (cu ft)| Variable | Definition & Basis |
|---|---|
| Weight (lb) | Total gross weight of cargo including pallets and packaging |
| Volume (ft³) | Cubic feet = (Length × Width × Height in inches) ÷ 1,728 |
| Class | Class rating (50 to 400) derived from the 13-sub density table |
Worked Example: Standard Pallet Shipment (2 Pallets)
A shipper is dispatching 2 standard 48 × 40 × 48 inch pallets weighing 600 lb each (1,200 lb total).
Input Parameters
- Pallet Dimensions48 × 40 × 48 in each (2 pallets)
- Weight per Pallet600 lb
- Total Weight1,200 lb
Step-by-Step Calculation Breakdown
- 1Calculate cubic volume per pallet: (48 × 40 × 48) ÷ 1,728 = 53.33 ft³.
- 2Calculate total shipment volume: 53.33 ft³ × 2 = 106.67 ft³.
- 3Calculate density: 1,200 lb ÷ 106.67 ft³ = 11.25 lb/ft³ (PCF).
- 4Look up density in the 13-sub table: 10 to <12 lb/ft³ maps to Freight Class 92.5.
Assumptions Used
- Dimensions must reflect the outermost dimensions of the packaged freight ready to ship.
- Density uses total gross weight including pallet bases and banding.
- Uses the NMFTA 13-sub full-scale density scale (July 2025 standard).
Important Limitations
- This tool calculates an ESTIMATED density-based freight class only.
- Official NMFC item classification also evaluates handling ease, stowability, liability (value/perishability), and item-specific tariff provisions.
- This website does not provide official NMFC code lookups.
Authoritative Standards & Sources
The 13 density-to-class bands used on this site match the structure published for density-based classification. Further commodity groups continue to be evaluated by NMFTA.
Frequently Asked Questions
What is freight class?
Historically, the National Motor Freight Classification (NMFC) catalog defined 18 numerical classes ranging from Class 50 (densest) to Class 500 (lightest) based on four transport characteristics: density, stowability, handling, and liability. In contrast, this calculator evaluates shipment density against the standardized 13-subprovision density structure (ranging from Class 50 up to Class 400) widely used across North American LTL rating. Official commodity-specific NMFC classifications are assigned exclusively by NMFTA tariffs for specific item numbers—which may include non-density factors or fixed ratings—and cannot be determined by mathematical density alone.
Is density the only factor determining freight class?
No. While NMFTA reforms and carrier rules tariffs increasingly map general freight to the standardized 13-subprovision density scale, official NMFC commodity classifications still govern items with specific catalog codes. Official classification evaluates all four historical transport characteristics—density, handling, stowability, and liability (such as perishability, hazardous materials, or high theft value). This calculator provides a mathematical density-based estimate; shipments governed by commodity-specific item numbers or carrier exception tariffs may be rated differently.
How do I avoid freight re-classification penalties?
Accurately measure the outermost bulges of your pallets (including overhang and pallet height) and weigh the shipment on a certified scale. Under-reporting dimensions or weight frequently results in carrier re-weigh and re-measurement inspection fees.
What to Calculate Next
Freight planning connects sequentially from package dimensions to freight class, pallets, and full equipment: