How is NMFC freight class determined for LTL shipments?

Freight class is primarily determined by density (pounds per cubic foot). Divide your shipment weight in lbs by its volume in cubic feet to get the PCF value. Less dense goods receive a higher class number and a higher LTL rate. Some commodities have NMFC exception items that assign a fixed class regardless of density based on stowability, liability, and handling characteristics.

What is the difference between freight class 50 and class 500?

Class 50 is the lowest and cheapest, applying to the densest goods (50+ lbs/cu ft) such as steel, cast iron, or sand. Class 500 is the highest and most expensive, applying to ultra-low-density goods (under 1 lb/cu ft) like feathers or expanded foam. Most general freight falls between class 70 and class 125.

Can freight class be negotiated with my LTL carrier in Canada?

Yes, in some cases. If your commodity has an NMFC exception item, you can reclassify it with proper documentation from the NMFC directory. Some carriers offer FAK (Freight All Kinds) pricing that rates all commodities at a flat negotiated class, simplifying billing for shippers with diverse product mixes. Contact your freight broker to explore your options.

Freight Tool

Freight Density &
Class Calculator

Calculate shipment density and get an estimated freight class for LTL planning. Enter your dimensions and weight below.

Results are density-based estimates for general planning only. Official NMFC classification depends on commodity item, carrier rules, and shipment characteristics. Confirm class with your carrier before booking.

New to freight class? See definition · What is NMFC?

Quick Presets— pre-fill all fields instantly

Measurement Units:

Handling Unit 1

Qty

Packaging Type

Length (in)

Width (in)

Height (in)

Weight per piece (lbs)

Shipment Characteristics

Commodity Description (optional)

Stackable?

Fragile?

High Value?

Temperature-Controlled?

Understanding Freight Class

Freight class (NMFC class) is the standardized system used by LTL carriers across North America to classify goods for pricing. Classes range from 50 (lowest cost, densest freight) to 500 (highest cost, lightest and most difficult to handle). The four factors that determine class are: density, stowability, handling, and liability.

Density is the most common factor and is calculated by dividing total shipment weight (in lbs) by total cubic footage. However, the final class is assigned based on the official NMFC commodity item for your specific product — not density alone. Carriers may reclassify your shipment during inspection if the declared class does not match their assessment.

Density range shown above is for general reference. When in doubt, contact your LTL carrier or freight broker to confirm the correct NMFC class for your commodity before booking.

Frequently Asked Questions

Is the class shown guaranteed by the carrier?

No. This calculator provides a density-based estimate only. Your LTL carrier may inspect the shipment and reclassify it if the declared class does not match their assessment. A reclassification charge (also called an "inspect and reweigh") may apply.

What is the difference between density class and NMFC class?

Density-based class uses only weight and dimensions. NMFC class considers the specific commodity item number, which accounts for density plus handling difficulty, stowability, and liability. For many standard goods, density and NMFC class align closely. For fragile, regulated, or unusual commodities, they may differ significantly.

Does shipment class affect all-in freight rates the same way?

OTR Logistics Solutions quotes all-in flat rates rather than using a published tariff multiplied by class. However, freight class is still used by LTL carriers internally and affects their pricing. Higher classes generally cost more to move per hundredweight.

Why does my class matter if I'm doing FTL?

Full truckload freight is typically quoted by the load and does not use freight class for pricing. Freight class matters primarily for LTL (less-than-truckload) shipments.

How do I reduce a high freight class?

The most effective strategies are: increasing density through denser packaging or removing empty space, combining multiple light packages onto fewer pallets, and using inner packaging to reduce the effective cube. In some cases, choosing a different shipping mode (e.g., partial truckload) avoids class-based pricing entirely.

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OTR Logistics Solutions matches your freight class to vetted LTL and FTL carriers across Canada and the US.

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Related Guide

Freight Brokerage

How Freight Class Is Calculated (and Why It Changes Your Rate)

6 min read

About this tool

What it calculates

Calculates freight density (pounds per cubic foot) from your shipment dimensions and weight, then maps density to the appropriate NMFC freight class for LTL pricing.

Who it's for

Shippers booking LTL freight who need to declare a freight class on the bill of lading or get an accurate LTL rate quote.

What you'll need

Item dimensions (length × width × height in inches or cm) and actual weight (lbs or kg). Enter multiple items to calculate a blended average.

How to use the result

Use the calculated class as the declared class on your LTL BOL. Carriers may inspect and reclassify at pickup or delivery — a reclassification charge applies if the actual class differs.

Key assumptions

Class is calculated using density only (NMFC density table). Commodity-specific NMFC items may have a fixed class that differs from the density-based estimate — especially for fragile, hazardous, or high-liability goods.

When to confirm with a specialist

If your commodity has a specific NMFC item number with a fixed class (e.g. electronics, pharmaceuticals, or artwork), confirm the class with your carrier or OTR Logistics Solutions before booking.

Need help with this shipment?

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