Dimensional weight calculator
Find the volumetric weight a carrier bills you for, and compare it to the actual weight.
How it works
Dimensional weight = (length × width × height) ÷ divisor. The divisor encodes the carrier’s assumed density and depends on the units (cm³/kg or in³/lb). Your billable weight is the larger of the actual weight and the dimensional weight, which is why a big, light box can cost more to ship than a small, heavy one.
FAQ
What is dimensional weight?
Carriers charge for the greater of a parcel’s actual weight and its “dimensional” weight — a figure derived from its volume. It stops light-but-bulky boxes from shipping cheaply.
What divisor should I use?
It depends on the carrier and units. Common air/express divisors are 5000 (cm³ per kg) or 139 (in³ per lb) for UPS/FedEx; some domestic ground services use 166 in³/lb. Always confirm with your carrier’s current rate card.
Which weight am I actually billed on?
The “billable weight” — whichever is higher, actual or dimensional, rounded up per the carrier’s rules.
Divisors and rounding rules vary by carrier and change over time — confirm on the carrier’s current rate card.