FedEx Dimensional Weight & Cost Estimator
Calculate your billable weight and estimated shipping costs based on package dimensions.
Calculation Summary
*Disclaimer: This is an estimate based on standard FedEx dimensional factors and base rates. Actual pricing may vary based on fuel surcharges, residential delivery fees, and specific discounts.
How to Calculate FedEx Shipping Costs
Shipping with FedEx involves more than just weighing your box on a scale. FedEx, like most major carriers, uses a method called Dimensional Weight (Dim Weight) to determine shipping prices. This ensures they are compensated for the space a package occupies in their trucks and planes, not just its mass.
What is Dimensional Weight?
Dimensional weight is a calculation that converts the volume of a package into a theoretical weight. If your package is large but very light (like a box filled with pillows), FedEx will charge you based on the box's size rather than its actual weight.
The FedEx Dim Weight Formula:
(Length x Width x Height) / Dim Factor = Dimensional Weight
For most FedEx services, the standard divisor (Dim Factor) is 139. If you are using retail rates at a FedEx Office location, the divisor may be 166.
Understanding Billable Weight
FedEx compares the Actual Weight of the package to the Dimensional Weight. Whichever number is higher becomes the Billable Weight. This is the weight used to determine the final shipping rate.
Tips for Reducing FedEx Shipping Costs
- Minimize Box Size: Use the smallest box possible to fit your items securely. Even reducing one dimension by an inch can significantly drop the dimensional weight.
- Use FedEx One Rate: For small, heavy items, FedEx One Rate (flat rate shipping) can often be cheaper than weight-based shipping.
- Consolidate Shipments: Shipping one larger box is often more cost-effective than shipping two smaller boxes.
- Check your Divisor: High-volume shippers can often negotiate a higher Dim Factor (e.g., 250), which lowers the dimensional weight and reduces costs.
Real-World Example
Suppose you are shipping a box that weighs 5 lbs but measures 18″ x 18″ x 12″.
- Actual Weight: 5 lbs
- Cubic Size: 18 x 18 x 12 = 3,888 cubic inches
- Dim Weight: 3,888 / 139 = 27.97 lbs (Rounded up to 28 lbs)
- Billable Weight: 28 lbs
In this scenario, you would be charged for 28 lbs even though the box only weighs 5 lbs! Using our FedEx calculator helps you spot these discrepancies before you ship.