Shipping Guide

Freight Class Explained: How to Determine Your NMFC Code

JC
Jeff Conboy

Freight Logistics Specialist

6 min read

Freight class is confusing—but getting it wrong can cost you big. After seeing countless shippers overpay (or get hit with reclassification fees), here's what you actually need to know.

What is Freight Class?

Freight class is a standardized classification system for LTL (Less-Than-Truckload) shipping. It ranges from Class 50 (cheapest) to Class 500 (most expensive) and determines how much you pay per hundred pounds (CWT).

The classification comes from the NMFC (National Motor Freight Classification), which assigns codes to virtually every type of commodity based on four factors.

The 4 Factors That Determine Class

1. Density

Weight per cubic foot. Denser = lower class = cheaper. A pallet of steel (dense) costs less to ship than a pallet of pillows (not dense).

2. Stowability

How easily can it be stored with other freight? Regular pallets are easy. Odd shapes, hazmat, or items that can't be stacked are harder.

3. Handling

Does it require special care? Fragile items, items needing special equipment, or careful loading cost more to handle.

4. Liability

Risk of damage or theft. High-value electronics have higher liability than concrete blocks. More risk = higher class.

Freight Class Chart

Class Density (lbs/cu ft) Example Products
50 50+ Steel, bricks, cement
55 35-50 Construction materials
60 30-35 Car parts, bottled beverages
65 22.5-30 Car accessories, boxed books
70 15-22.5 Food items, auto engines
77.5 13.5-15 Tires, bathroom fixtures
85 12-13.5 Machine parts, crated items
92.5 10.5-12 Computers, monitors
100 9-10.5 Furniture, crates
110 8-9 Cabinets, table saws
125 7-8 Small appliances
150 6-7 Auto sheet metal
175 5-6 Clothing, couches
200 4-5 TVs, packaged mattresses
250 3-4 Bamboo furniture, mattresses
300 2-3 Model boats, kayaks
400 1-2 Ping pong balls
500 <1 Gold dust, ping pong balls

How to Find Your Freight Class

Method 1: Calculate Density

For most products, density is the main factor. Here's how to calculate it:

Density = Weight ÷ Cubic Feet

Cubic Feet = (Length × Width × Height) ÷ 1,728

Example: A pallet is 48" × 40" × 48" and weighs 500 lbs.

  • Cubic feet = (48 × 40 × 48) ÷ 1,728 = 53.3 cu ft
  • Density = 500 ÷ 53.3 = 9.4 lbs per cubic foot
  • Based on the chart, this is Class 100

Method 2: Look Up NMFC Code

Many products have specific NMFC codes regardless of density. You can look these up in the NMFC database (requires subscription) or ask your broker.

From my experience: Don't guess your freight class. If you ship Class 85 but the freight is actually Class 125, the carrier will reclassify it and bill you the difference—plus a reclassification fee. I always verify the NMFC code before quoting.

Why Freight Class Matters

The difference between classes can be dramatic. Here's a real example for a 500 lb shipment from Chicago to Dallas:

  • Class 70: ~$280
  • Class 100: ~$420
  • Class 150: ~$650
  • Class 200: ~$890

Same weight, same lane—3x price difference based purely on freight class.

Pro tip: If your freight is close to a class boundary, consider repackaging to increase density. Adding a few more items to a pallet (if they fit) can sometimes bump you to a lower class and save money.

Common Freight Class Mistakes

  • Using the wrong NMFC code: Leads to reclassification and extra charges
  • Not measuring accurately: Dimensional weight can change your class
  • Ignoring packaging: How you pack affects the calculation
  • Assuming all items are the same: Mixed pallets need careful classification

The Bottom Line

Freight class directly impacts your shipping cost. Take time to measure accurately, find the right NMFC code, and verify before shipping. When in doubt, ask your broker—we deal with this daily and can help you classify correctly.

Not Sure About Your Freight Class?

Submit your shipment details including product description, weight, and dimensions. I'll determine the correct freight class and get you accurate quotes.

JC

Written by

Jeff Conboy

Freight Logistics Specialist

Freight industry professional with hands-on experience in LTL, FTL, flatbed, and refrigerated shipping. Helping businesses find the right carriers at the right prices.

View full profile

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