Shipping Cost Calculator
Estimate shipping cost based on your package's actual weight, dimensions, and carrier rate — accounting for dimensional weight pricing.
What dimensional weight means
Most major carriers charge based on whichever is greater: a package's actual weight or its 'dimensional weight' — a calculated figure based on the box's size, meant to account for the fact that large, lightweight packages take up valuable truck and plane space regardless of how little they weigh.
This calculator uses the widely used divisor of 166 (common for domestic US shipments) to calculate dimensional weight from length × width × height in inches. Some carriers and international shipments use a different divisor (like 139), so check your specific carrier's published formula for precise quotes.
Why oversized-but-light packages cost more than expected
This is the most common shipping cost surprise for e-commerce sellers — a large, lightweight item (like a lampshade or a pillow) can trigger a dimensional weight charge far higher than its actual weight would suggest, since the box's volume, not just its contents' weight, drives the cost.
Using the smallest reasonable packaging for a given item is one of the most effective ways to control shipping costs, since reducing box dimensions directly reduces dimensional weight, even when actual product weight stays the same.
Frequently asked questions
Why would I be charged for a heavier weight than my package actually weighs?
If your package is large relative to its actual weight, carriers charge based on 'dimensional weight' instead — a size-based calculation designed to account for the space large packages take up in transport, regardless of how light they are.
Does every carrier use the same dimensional weight divisor?
No — 166 is common for many US domestic shipments, but some carriers and international services use different divisors (like 139), so check your specific carrier's published rates for the most accurate estimate.