Seventeen carriers across five continents. Two unit systems. One billable number that decides what your package actually costs to ship.
Awaiting dimensions. Enter package details to compute billable weight.
Carriers invented DIM weight to charge fairly for packages that hog truck space but weigh little. A pillow-filled box and a lead brick of the same size take up identical room — so they cost the same to ship.
Volume divided by a number — typically 139 for US carriers, 5000 for metric. Smaller divisor means higher DIM weight. The number itself isn't physics. It's a business choice each carrier makes.
Carriers compute both your actual weight (the scale number) and your dimensional weight (the box-size number). The bigger one becomes your billable weight.
Thirty side-by-side comparisons — same package, two carriers, see which one wins. Each comparison page has a live calculator locked to the two carriers being compared.