Freight Class Calculator
Determine the correct freight class for your shipments based on density, stowability, handling, and liability. Our calculator helps logistics professionals estimate freight class to avoid reclassification fees and ensure accurate shipping quotes.
Calculate Your Freight Class Calculator
What is Freight Class?
Freight class is a standardized categorization system used in the shipping industry to determine transport costs for Less Than Truckload (LTL) freight. Established by the National Motor Freight Traffic Association (NMFTA), freight classes range from 50 (lowest) to 500 (highest) and are primarily based on the shipment's density, though other factors are also considered.
The lower the freight class number, the lower the shipping cost will typically be for that item.
How Freight Class is Determined
While our calculator focuses on density as the primary factor, freight class is officially determined by four characteristics:
1. Density
The weight of the shipment relative to its volume (pounds per cubic foot). Denser items generally have lower freight classes and lower shipping rates.
2. Stowability
How easily the freight can be stored and transported alongside other items. Factors that affect stowability include:
- Irregular shapes
- Excessive length or protrusions
- Hazardous properties
- Weight distribution
3. Handling
Special requirements for loading, transporting, and unloading the freight. Items that require special equipment, care, or procedures will typically have higher freight classes.
4. Liability
The likelihood of the freight being damaged, stolen, or causing damage to other freight. This includes considerations like:
- Value per pound
- Fragility
- Perishability
- Potential for theft
Understanding Freight Class Numbers
There are 18 standard freight classes ranging from 50 to 500. Here's what they generally represent:
| Class | Density (lbs/ft³) | Example Items |
|---|---|---|
| 50 | 50+ | Steel, brick, cement, hardwood flooring (on pallets) |
| 55 | 35-50 | Bricks, cement, hardwood flooring, construction materials |
| 60 | 30-35 | Car accessories, steel cables, used machinery |
| 65 | 22.5-30 | Car parts, books, bottled beverages |
| 70 | 15-22.5 | Car engines, food items, hardware |
| 77.5 | 13.5-15 | Tires, bathroom fixtures |
| 85 | 12-13.5 | Crated machinery, cast iron stoves |
| 92.5 | 10.5-12 | Computers, monitors, refrigerators |
| 100 | 9-10.5 | Boat covers, car covers, canvas |
| 110 | 8-9 | Cabinets, framed artwork, table saws |
| 125 | 7-8 | Small appliances, end tables |
| 150 | 6-7 | Auto sheet metal, bookcases |
| 175 | 5-6 | Clothing, couches, stuffed furniture |
| 200 | 4-5 | Sheet metal, aluminum table, packaged mattresses |
| 250 | 3-4 | Mattresses and box springs, plasma TVs |
| 300 | 2-3 | Wood cabinets, tables, chairs, assembled furniture |
| 400 | 1-2 | Deer antlers, basketballs, ping pong tables |
| 500 | Less than 1 | Light items that take up a lot of space (ping pong balls, styrofoam) |
Why Freight Class Matters
Accurate Shipping Costs
Using the correct freight class ensures you get accurate quotes and aren't surprised by reclassification fees later. Incorrect classification can lead to significant cost adjustments after shipping.
Proper Handling
Each freight class has associated handling guidelines that help ensure your items are transported safely and efficiently, reducing the risk of damage.
Efficiency
The system helps carriers optimize their operations by understanding what they're transporting, leading to more efficient logistics planning and potentially faster delivery times.
Standardization
The NMFC system creates a standardized approach that allows for fair comparison of shipping rates across different carriers for similar items.
Tips for Optimizing Your Freight Class
- Package efficiently: Where possible, maximize density by using appropriate packaging materials and minimizing empty space.
- Consider palletizing: Putting items on pallets can sometimes lower your freight class, especially if it improves density and handling.
- Accurate measurements: Always provide precise dimensions and weight. Being off by even a small amount can result in reclassification and additional charges.
- Consult the NMFC: For the most accurate classification, check the specific NMFC item number for your product, as there are over 18,000 classified items.
- Work with experts: Freight class can be complex, so consider consulting with freight brokers or 3PL providers who specialize in this area.
Beyond Freight Class: Other Factors That Affect Shipping Costs
While freight class is important, it's not the only factor that determines your shipping costs:
Distance
Longer distances generally mean higher shipping costs, though the cost per mile typically decreases as distance increases.
Fuel Surcharges
These fluctuate with fuel prices and are added to the base shipping rate.
Accessorial Services
Additional services like liftgate delivery, inside delivery, limited access locations, or residential delivery will incur extra fees.
Dimensional Weight
For very light but bulky items, carriers may charge based on dimensional weight rather than actual weight.
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Frequently Asked Questions
Freight class is important because it:
- Directly affects your shipping costs
- Helps carriers understand what they're transporting
- Ensures proper handling of your goods
- Standardizes pricing across the industry
When it's most accurate:
- For standard, regularly shaped items
- When handling requirements are normal
- For items without special liability concerns
When it may not be accurate:
- Fragile items (may have higher class regardless of density)
- Hazardous materials (special classifications apply)
- Items with irregular shapes that affect stowability
- High-value goods that create increased liability
For the most accurate classification, always refer to the NMFC (National Motor Freight Classification) guide or consult with your carrier.
- Reclassification fees: Carriers routinely inspect shipments and will adjust your charges if they find your freight class is incorrect
- Additional charges: If your actual freight class is higher than what you declared, you'll be charged the difference plus a potential penalty fee
- Shipping delays: Discrepancies may result in your shipment being held until fee disputes are resolved
- Audit issues: Systematic misclassification can trigger carrier audits of all your shipments
Conversely, if you consistently use a higher freight class than necessary, you'll be overpaying for shipping and reducing your profit margins unnecessarily.
This relationship exists because:
- Denser items utilize truck space more efficiently
- Denser items are generally more stable and easier to secure
- Carriers can transport more weight with denser cargo
For example:
- A steel block (very dense) might be Class 50
- A refrigerator (moderate density) might be Class 92.5
- Ping pong balls (very low density) might be Class 400
Density is calculated by dividing weight (in pounds) by volume (in cubic feet). The resulting number (pounds per cubic foot) directly correlates to specific freight classes.
Key points about NMFC codes:
- Each NMFC code is tied to a specific freight class
- The NMFC contains approximately 18,000 product classifications
- NMFC codes are typically 6-7 digits (e.g., 156600 for office chairs)
- They provide much more granular classification than freight class alone
Using the correct NMFC code when shipping ensures the most accurate freight class assignment and pricing. These codes are maintained by the National Motor Freight Traffic Association and updated regularly to reflect changes in products, packaging, and shipping methods.
- Increase density: Use more compact packaging, remove unnecessary packaging material, or redesign products to be more dense
- Palletize shipments: Properly secured palletized freight often qualifies for lower freight classes than loose items
- Consider packaging changes: How items are packaged can affect their classification (e.g., disassembled vs. assembled furniture)
- Consolidate shipments: Combining multiple items can sometimes achieve a better overall density
However, it's important to note that you should never misrepresent your shipment to obtain a lower class. Carriers routinely inspect freight, and misclassification can result in significant additional charges and damaged business relationships.
LTL Shipping:
- Freight class is a critical pricing factor
- Each shipment is classified individually
- Carriers combine multiple shippers' freight in one truck
- Pricing is based on weight, dimensions, freight class, and distance
FTL Shipping:
- Freight class is generally not used for pricing
- Pricing is typically based on a flat rate per mile
- The shipper pays for the entire truck regardless of how full it is
- Weight limitations still apply (legal road limits)
This difference exists because FTL shipping is selling the entire truck capacity to one shipper, while LTL carriers need a standardized way to compare different types of freight that will share space on the same truck.
- Major updates are typically released three times per year
- These updates may include reclassification of existing items
- New products are added to the classification
- Some classifications may be eliminated or consolidated
These updates reflect changes in shipping practices, packaging technologies, product designs, and transportation equipment. Businesses that ship freight regularly should stay informed about these updates, especially for products they ship frequently, as changes can significantly impact shipping costs.
Many freight brokers and 3PL providers offer subscription services that notify customers of relevant changes to freight classifications that might affect their shipping costs.
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