Freight Class Explained: How to Classify Your LTL Shipments
Learn how freight class works, how it affects your shipping costs, and how to determine the correct classification for your products.
Sarah Mitchell•Apr 20, 2023Understanding freight class is essential for anyone shipping LTL freight. It directly impacts your shipping costs and can lead to expensive reclassification fees if done incorrectly.
What is Freight Class?
Freight class is a standardized classification system created by the National Motor Freight Traffic Association (NMFTA). It categorizes commodities for shipping purposes, with classes ranging from 50 to 500.
Lower class numbers (50-85) = Lower shipping rates Higher class numbers (125-500) = Higher shipping rates
The Four Factors That Determine Freight Class
1. Density
Density is the most important factor. It’s calculated by dividing the weight of your shipment by its volume (pounds per cubic foot).
- Higher density = Lower freight class = Lower cost
- Lower density = Higher freight class = Higher cost
2. Stowability
How easily can your freight be stored alongside other items? Irregularly shaped items or those that can’t be stacked are harder to stow and may receive a higher class.
3. Handling
Does your freight require special equipment or careful handling? Fragile items, hazardous materials, or oversized pieces typically have higher freight classes.
4. Liability
What’s the risk of damage or theft? High-value, perishable, or easily damaged goods often receive higher classifications.
Common Freight Classes and Examples
| Class | Density (lbs/cu ft) | Example Products |
|---|---|---|
| 50 | 50+ | Sand, bricks, cement |
| 70 | 15-22.5 | Car parts, food items |
| 85 | 12-13.5 | Machinery, cast iron |
| 100 | 9-10.5 | Furniture, boat covers |
| 125 | 7-8 | Small appliances |
| 175 | 4-6 | Clothing, couches |
| 250 | 2-3 | Bamboo furniture, mattresses |
| 500 | Less than 1 | Ping pong balls, gold dust |
How to Calculate Your Freight Class
- Measure your shipment: Length x Width x Height (in inches)
- Convert to cubic feet: Divide by 1,728
- Calculate density: Weight (lbs) ÷ Cubic feet
- Look up the class: Use the NMFC database or a freight class calculator
Why Getting It Right Matters
Incorrectly classifying your freight can result in:
- Reclassification fees: Carriers inspect shipments and will charge extra if the class is wrong
- Unexpected invoices: You may be billed for the difference weeks after delivery
- Delayed shipments: Disputes can hold up your freight
How FreightSimple Helps
Our platform automatically helps you determine the correct freight class based on your product information. We also audit all bills to catch any incorrect reclassification charges before you pay them.
Ready to ship with confidence? Get started with FreightSimple today.
Frequently Asked Questions
What is freight class?
Freight class is a standardized classification system created by the National Motor Freight Traffic Association (NMFTA) that categorizes commodities for LTL shipping. Classes range from 50 to 500, with lower numbers meaning lower shipping rates. The class is determined by four factors: density, stowability, handling difficulty, and liability.
How does freight class affect shipping costs?
Freight class directly determines your LTL shipping rate. Lower freight classes (50-85) result in lower per-pound shipping costs because these items are dense, easy to handle, and unlikely to be damaged. Higher classes (125-500) cost more because those items are lighter, bulkier, or more fragile.
What happens if I use the wrong freight class?
Using the wrong freight class can result in a reclassification by the carrier, which typically means a higher rate plus an inspection fee. Carriers weigh and measure shipments at terminals and will adjust the class if it doesn't match. Always verify your NMFC code and freight class before shipping.
How do I determine my freight class?
To determine your freight class, you need to know your product's NMFC (National Motor Freight Classification) code. You can look this up in the NMFC database by product type, or calculate it based on density (weight divided by volume in cubic feet). FreightSimple automatically helps you find the right class when you get a quote.