Dimensional weight calculator

Dimensional weight FAQ

What is dimensional weight?

Dimensional (DIM) weight is a pricing measure that accounts for how much space a package takes up rather than just how heavy it is. A large, light box can cost more to ship than a small, heavy one because it fills trailer and aircraft space that the carrier could otherwise sell. Carriers bill the greater of your package's actual weight and its dimensional weight, so an oversized box gets charged for the room it occupies.

How do DIM divisors work for UPS, FedEx, USPS and DHL?

To find dimensional weight you multiply length × width × height in inches and divide by the carrier's DIM divisor. UPS and FedEx use a divisor of 139 for domestic shipments, USPS uses 166 for applicable Priority Mail, and DHL typically uses 139 as well. A smaller divisor produces a larger dimensional weight, which is why the same box can have a different billable weight from one carrier to the next.

What is billable weight and how is it calculated?

Billable weight is the number the carrier actually charges you for — it is the greater of your package's actual weight and its dimensional weight, rounded up to the next pound. Enter your box dimensions and real weight above and the calculator shows the billable weight for each carrier. If dimensional weight is higher than actual weight, you are paying for empty space inside the box.

How can I lower my dimensional weight charges?

Use a box that fits the contents snugly — every extra inch in any dimension raises dimensional weight. Cut down oversized cartons, switch to poly mailers for soft goods, and avoid padding the void with bulky filler. Even shaving one dimension can drop you below a billable-weight threshold. Compare live carrier rates with the right box size before you buy the label so the dimensional charge does not surprise you on the invoice.