What is dimensional weight?
Airlines and parcel van networks are limited by space as much as by kilograms. A box of pillows can fill a container and still weigh very little. To stop light, bulky parcels crowding out dense ones, carriers invented dimensional weight (also called volumetric weight).
The idea is simple: they pretend the box weighs a figure based on its volume. You are charged the higher of that figure and the number on the scale. That higher number is the billable weight.
The formula is:
Dimensional weight = (length × width × height) ÷ divisor, then rounded up to the next whole kilogram or pound.
The divisor is just a policy number. A smaller divisor means a heavier dim weight for the same carton — UPS Daily at 139 will bill more than USPS Priority at 166 for the same light, bulky box. Measure the longest point on each side, including padding and bulges, in the unit the carrier uses.
Figures and divisors on this site were checked on 12 November 2026 against the carriers’ public explanations. Contracts, countries and services sometimes use a different divisor, so treat the result as a plan, not an invoice.