Volumetric Weight Explained

Dimensional weight — also called DIM weight or volumetric weight — is a way of pricing a shipment based on how much space it takes up, not just how heavy it is. It’s calculated by multiplying a package’s length by its width by its height, then dividing by a carrier divisor.

Actual weight and dimensional weight are different things. Actual weight is what your shipment weighs on a scale. Dimensional weight represents the space it occupies in a truck or plane, including packaging.

Carriers bill based on chargeable weight — the greater of your shipment’s actual weight or its dimensional weight. This is why a large, lightweight box can sometimes cost more to ship than a small, heavy one: it’s taking up more space in transit, even if it doesn’t weigh much.

Our quote tool calculates dimensional weight the same way, for every shipment:

• Inches / Pounds: Length × Width × Height ÷ 139
• Centimeters / Kilograms: Length × Width × Height ÷ 5000

For example, an 18 × 18 × 16 inch box has a dimensional weight of 18 × 18 × 16 ÷ 139 ≈ 37.29 lb. If the package’s actual weight is less than that, you’ll be charged for 37.29 lb — the dimensional weight, since it’s the greater number.

• Right-size your box.Using a box that’s much bigger than your item increases dimensional weight (and cost) for no reason.
• Minimal, appropriate packaging keeps both your dimensional weight and your shipping cost down.
• It’s automatic. When you enter your package dimensions in our quote tool, chargeable weight is calculated for you in real time.