Freight Class Calculator
Summary Result
Class 85
Density-based estimate
Class 400lower density
12 to under 15 lb/ft³
Class 85higher density
Hazmat LTL Shipping Guide
Hazmat Freight Class
Key Hazmat Freight Facts
Hazmat freight class and DOT hazard class are separate classifications. The DOT hazard class identifies the transportation hazard, while LTL freight class is used for freight classification and pricing.
- Nine DOT hazard classes: hazardous materials are grouped into Classes 1 through 9 based on the type of transportation hazard they present.
- Packing Groups I–III: where assigned, the packing group indicates the degree of danger: I for great danger, II for medium danger, and III for minor danger.
- Packing group is not freight class: PG I, II, or III does not translate to a specific LTL freight class number.
- Use finished shipment measurements: enter the outside packaged dimensions and total packaged weight when estimating density-based freight class.
Freight Planning Tools
Use the freight class calculator and interactive freight class chart to plan packaged hazmat shipments.
Interactive Freight Class Chart
13 lb/ft³Selected density
Class 400lower density
Class 50higher density
Hazmat freight class calculator
Estimate Your Hazmat Freight Class
A palletized hazmat shipment is preloaded as an example. Replace the outside dimensions and total packaged weight with your shipment measurements.
Your result
Cubic feet
53.33
Density
13.13
lb/cu ft
Estimated freight class
85
Density-based estimate for the preloaded hazmat shipment example.
Density planning examples
Hazmat Freight Class Examples
These examples show how finished package size and weight change a density-based freight class estimate. They do not assign a freight class to a specific hazardous material or DOT hazard class.
Dense palletized shipment
Illustrative finished shipping unit
48 × 40 × 36 in
Packaged weight: 1,200 lb
- Cubic feet
- 40.00
- Density
- 30.00
- lb/cu ft
Estimated class
Density-based
60
Medium-density pallet
Illustrative finished shipping unit
48 × 40 × 48 in
Packaged weight: 700 lb
- Cubic feet
- 53.33
- Density
- 13.13
- lb/cu ft
Estimated class
Density-based
85
Lower-density protected shipment
Illustrative finished shipping unit
48 × 48 × 48 in
Packaged weight: 450 lb
- Cubic feet
- 64.00
- Density
- 7.03
- lb/cu ft
Estimated class
Density-based
125
DOT hazard class vs LTL freight class
How Hazardous Materials Freight Class Works
A DOT hazard class describes the transportation hazard presented by a material. LTL freight class is a separate freight-classification system. A shipment identified as Class 3, Class 8, or another DOT hazard class does not automatically receive the same numbered LTL freight class.
DOT classification
Hazard Class
Identifies the type of transportation hazard. The nine classes include explosives, gases, flammable liquids, flammable solids, oxidizers and organic peroxides, toxic and infectious substances, radioactive materials, corrosives, and miscellaneous hazardous materials.
LTL classification
Freight Class
Used for LTL freight classification and pricing. Density can be part of the class determination, while applicable commodity provisions and shipment characteristics may also affect final classification.
DOT hazard class ≠ LTL freight class.
Hazard classification reference
The 9 DOT Hazard Classes
The U.S. Department of Transportation groups hazardous materials into nine hazard classes. Several classes are further divided into divisions.
| DOT Class | Hazard category | Divisions / description |
|---|---|---|
| Class 1 | Explosives | Divisions 1.1 through 1.6 |
| Class 2 | Gases | Divisions 2.1, 2.2, and 2.3 |
| Class 3 | Flammable liquids | Flammable liquid hazards |
| Class 4 | Flammable solids | 4.1 flammable solid, 4.2 spontaneously combustible, 4.3 dangerous when wet |
| Class 5 | Oxidizers and organic peroxides | 5.1 oxidizer, 5.2 organic peroxide |
| Class 6 | Toxic and infectious substances | 6.1 toxic materials, 6.2 infectious substances |
| Class 7 | Radioactive materials | Radioactive materials |
| Class 8 | Corrosive materials | Corrosive materials |
| Class 9 | Miscellaneous hazardous materials | Hazardous materials that meet Class 9 criteria |
Degree of danger
Hazmat Packing Groups I, II, and III
Packing groups indicate the degree of danger for hazardous materials when a packing group is assigned. Not every hazardous-material entry uses a packing group.
Packing Group I
Great Danger
Greatest degree of danger among the three packing groups.
Packing Group II
Medium Danger
Medium degree of danger.
Packing Group III
Minor Danger
Lowest degree of danger among the three packing groups.
Packing group does not determine LTL freight class.
Do not convert PG I, PG II, or PG III into a freight class number. Hazard classification, packing group, and LTL freight class answer different shipping questions.
Quote preparation
Hazmat Shipping Information for a Freight Quote
Hazmat shipments require information beyond dimensions and weight. Have the material description and shipment details available when requesting a carrier or broker quote.
Proper shipping name
Use the applicable hazardous-material shipping description.
UN, NA, or ID identification number
Provide the assigned identification number where applicable.
Hazard class or division
Identify the DOT hazard class and division when applicable.
Packing group
Include PG I, II, or III when a packing group is assigned.
Package count and type
Record the number and type of drums, cartons, containers, or other packages.
Quantity, dimensions, and weight
Provide total quantity plus the finished shipment dimensions and packaged weight used for freight planning.
Hazmat-specific shipment preparation
Hazmat Packaging and LTL Handling Requirements
Hazardous materials must be offered in packaging authorized for the material and prepared in accordance with applicable hazardous-material regulations. These requirements are separate from calculating freight density.
Authorized Packaging
Use packaging authorized for the material, including applicable specification, closure, filling-limit, and packing-group requirements.
Compatibility and Securement
Packaging materials must be compatible with their contents, and packages must be properly closed, cushioned, blocked, braced, and secured as required.
Marks, Labels, and Placards
Required package markings, hazard labels, shipping papers, emergency-response information, and vehicle placards depend on the material and shipment.
Freight Planning Calculators
Calculate and Plan Your Hazmat Shipment
Use the freight class, density, pallet, and linear-feet calculators for packaged LTL shipment planning.
Freight Class Calculator
Estimate freight class from packaged dimensions, weight, and density.
Freight Density Calculator
Calculate cubic feet and pounds per cubic foot for packaged freight.
Pallet Freight Calculator
Plan pallet dimensions, shipment weight, density, and configuration.
Freight Linear Feet Calculator
Estimate trailer-space usage for pallets and non-stackable freight.
Freight classes shown on this page are density-based estimates for shipment planning and do not determine whether a material is regulated as hazardous. Hazardous-material classification, packaging, marking, labeling, documentation, placarding, and carrier acceptance are governed separately. Confirm the final freight class with your carrier, broker, or official NMFC resources and verify hazmat requirements using current U.S. DOT regulations. NMFC® is a registered trademark of the National Motor Freight Traffic Association, Inc. FreightClassCalculator.tools is an independent calculator and is not affiliated with, endorsed by, or licensed by NMFTA.