Starting Jan. 2, FedEx will use a costlier price formula to calculate shipping rates for domestic air or ground parcels that's based on the package's dimensions, instead of actual weight, reported DC Velocity.
At present, the company calculates a package's dimensions by multiplying its length, width and height in inches and then dividing the total by 166. In January, that denominator will change to 139, causing a higher dimensional weight. The shipper will have to pay based on the parcel's dimensional or actual weight, which ever is higher.
The formula change represents an effort to increase compensation for handling lightweight, yet bulky packages that take up a large amount of space on a plane or ground vehicle.