Free tool
Freight class calculator: density to NMFC class
Enter your shipment's dimensions and weight and this tool calculates density in pounds per cubic foot, then shows the density-based NMFC class it falls into, with the full working shown, not just the answer.
By Aaron Brown, Founder & CEO · Reviewed by Aaron Brown · Published · Updated
Density is one of four factors, not the whole answer
NMFC freight classification is set by four characteristics: density, stowability, handling and liability. For most general commodities today, density does the majority of the work, but it does not determine class for every commodity, and the specific NMFC item that applies to your product, if one exists, governs over a density estimate. This calculator estimates the density-based class only. Confirm the actual class for hazardous materials, unusually fragile or oversized freight, or any commodity with its own named NMFC item, against NMFTA's ClassIT+ tool or your carrier before you book.
Enter your handling units
Every field in a group is for ONE handling unit (one pallet, crate or skid), including weight. Enter how many identical handling units make up that group separately; the calculator multiplies for you. If your shipment has handling units of a different size or weight, click “Add different handling unit” below rather than adding a second identical group. Density and class are not simply additive, so the calculator totals the cube and the weight across every group and divides once, the shipment-total method the NMFC uses when a shipment is billed as one combined figure.
Density
9 lbs/ft³
Estimated density-based class
Class 100
Show the working
- Cubic inches per unit = 48 × 40 × 45 = 86,400 in³
- Total cubic inches = 86,400 in³ × 1 unit = 86,400 in³
- Total cubic feet = 86,400 ÷ 1,728 = 50 ft³
- Total weight = 450 lbs × 1 unit = 450 lbs
- Density = 450 lbs ÷ 50 ft³ = 9 lbs/ft³
- 9 lbs/ft³ falls in the 8 to under 10 pcf band = Class 100
The full density-based class scale
This is the 13-band density progression NMFTA (the National Motor Freight Traffic Association) uses for general commodities with no unusual handling, stowability or liability characteristics, expanded from 11 to 13 bands under Docket 2025-1 (effective July 19, 2025) to add classes 50 and 55 for the densest freight. It is the same scale used in LanePilot's guide, How to Determine Freight Class.
| Density (lbs/ft³) | Class |
|---|---|
| 50 or more | Class 50 |
| 35 up to (but not including) 50 | Class 55 |
| 30 up to (but not including) 35 | Class 60 |
| 22.5 up to (but not including) 30 | Class 65 |
| 15 up to (but not including) 22.5 | Class 70 |
| 12 up to (but not including) 15 | Class 85 |
| 10 up to (but not including) 12 | Class 92.5 |
| 8 up to (but not including) 10 | Class 100 |
| 6 up to (but not including) 8 | Class 125 |
| 4 up to (but not including) 6 | Class 175 |
| 2 up to (but not including) 4 | Class 250 |
| 1 up to (but not including) 2 | Class 300 |
| 0 up to (but not including) 1 | Class 400 |
Source: NMFTA, Freight Classification Development Council, Docket 2025-1 (effective July 19, 2025). Treat these breakpoints as directional and confirm the current scale against NMFTA's ClassIT+ tool or your carrier's own density calculator before booking, since NMFTA periodically adjusts the exact scale through its docket process.
Go deeper on freight class and billing
How to Determine Freight Class walks through the full step-by-step process, including how to measure and weigh a shipment correctly.
NMFC Density-Based Reclassification: What Changed in 2026 covers the 2025-2026 rule changes behind this scale in full.
LTL freight quoting and booking for shippers calculates this same density and class automatically at quote time, no manual lookup needed.
Freight invoice audit and overcharge recovery catches it when the class on your invoice does not match the class on your original quote.
Common questions
How do I calculate freight density?
Measure one handling unit's length, width and height in inches, multiply them together, and divide by 1,728 to get cubic feet. Divide that unit's weight in pounds by its cubic feet, and the result is density in pounds per cubic foot (PCF). For a shipment of several identical handling units, this calculator multiplies the per-unit cube and weight by the unit count before dividing, the same total-weight-over-total-cube method the NMFC itself uses when a shipment is billed as one combined figure.
Does density alone determine my freight class?
No, and this is the most important thing on this page. NMFC classification is set by four characteristics: density, stowability, handling and liability. Density is the primary factor for most general commodities today, but it does not determine class for every commodity, and the specific NMFC item that applies to your product governs whenever one exists. This calculator estimates the density-based class only. Confirm the actual class for hazardous materials, unusually fragile, oversized or otherwise hard-to-handle freight, or any commodity with its own named NMFC item.
Is the class this calculator shows the exact class my carrier will bill?
Treat it as a strong estimate, not a guarantee. Carriers reweigh and remeasure freight at the terminal, and the density-based general scale this tool uses assumes no unusual handling, stowability or liability characteristics. Confirm your class against NMFTA's own ClassIT+ tool or your carrier's density calculator before you book, the same advice NMFTA gives directly.
Where does the density-to-class scale on this page come from?
NMFTA (the National Motor Freight Traffic Association), through its Freight Classification Development Council. The 13-band scale used here is the density progression NMFTA itself describes for general commodities with no unique handling, stowability or liability characteristics, expanded from an 11-band scale to 13 bands (adding classes 50 and 55 for the densest freight) under Docket 2025-1, effective July 19, 2025. It is the same scale used in LanePilot's own guide, How to Determine Freight Class.
Is weight entered per handling unit or for the whole shipment?
Per handling unit, consistently across every field on this page, length, width, height and weight are all for ONE handling unit within a group. Enter the number of identical handling units in that group separately and the calculator multiplies for you. Density and class are not simply additive across differing units, which is why, if your shipment has handling units of different sizes or weights, this calculator lets you add another group with the plus button rather than asking you to do that math yourself. It totals the cube and the weight across every group and divides once, the shipment-total method the NMFC uses when a shipment is billed as one combined figure.
Does this calculator book, quote or contact a carrier?
No. It only calculates density and estimates a class from the numbers you enter. It does not request a rate, tender a shipment, or communicate with any carrier. LanePilot is not a freight broker.
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