Everyday utility
Calculate DIM weight, billable weight, package volume, and when box size costs more than scale weight.
When to use this
It is built for ecommerce cartons, warehouse case packs, marketplace sellers, and lightweight products where box size can raise the billable weight.
Default result
The server-rendered 18 x 14 x 12 inch example has 22 lb DIM weight and bills at 22 lb instead of 8 lb actual weight.
Rounded dimensions
18 x 14 x 12 in
3,024 cubic inches.
Density
4.6 lb/cu ft
Lower density packages are more likely to be DIM billed.
Size check
70 in L+girth
14 lb above actual rounded weight.
The default example uses a 18 x 14 x 12 inch box, 8 lb actual weight, and the UPS Daily divisor 139.
Rounded dimensions are 18 x 14 x 12. Cubic inches are 18 x 14 x 12 = 3,024.
DIM weight is 3,024 / 139 = 21.8, rounded up to 22 lb.
Actual weight rounds to 8 lb. Billable weight is max(22, 8) = 22 lb, so the package bills 14 lb above actual weight.
DIM weight = rounded length x rounded width x rounded height / DIM divisor, rounded up to the next whole pound. Billable weight is usually the greater of rounded actual weight and rounded DIM weight.
Choose the divisor from the actual carrier, service, contract, marketplace, or warehouse tariff. UPS Daily, UPS Retail, and FedEx presets are included, but the divisor stays editable.
Right-size the carton, avoid excess void fill, trim unused height, compare box libraries, and test whether a mailer or smaller case pack protects the item safely.
Use the billable weight in your carrier rate tool with service, zone, fuel, residential, delivery area, oversized, and account-specific surcharges.
| Topic | Reference value | Source | Date | Note |
|---|---|---|---|---|
| UPS dimensional weight formula | UPS says to calculate dimensional weight by multiplying package length, width, and height, then dividing by the appropriate dimensional factor. | UPS dimensional weight guidance | As of June 20, 2026 | UPS pages distinguish Daily and Retail dimensional factors. Verify the current tariff for your account and service. |
| UPS divisors | UPS public guidance lists 139 for Daily rates and 166 for Retail rates in common U.S. planning examples. | UPS dimensional weight guidance | As of June 20, 2026 | The calculator keeps the divisor editable because account contracts, region, and service rules can differ. |
| FedEx dimensional weight formula | FedEx guidance describes dimensional weight as length x width x height divided by 139 for common U.S. and international package planning. | FedEx dimensional weight guidance | As of June 20, 2026 | FedEx guidance uses nearest-whole-inch dimensions in its public explanation; carrier tariffs can change. |
Dimensional weight, or DIM weight, is a billing weight based on package volume. Carriers compare DIM weight with actual weight and usually bill the greater value.
A large light box uses truck, aircraft, and warehouse space. DIM pricing charges for that space even when the scale weight is low.
Use the divisor from the carrier, rate type, contract, marketplace, or warehouse tariff that will bill the shipment. The included UPS and FedEx presets are starting points only.
Yes. Carrier rules usually require whole-inch dimensions. UPS public guidance commonly rounds up; FedEx public guidance describes nearest-whole-inch dimensions.
No. It calculates billable weight. To get dollars, enter the billable weight into the carrier rate table or shipping software with zone, service, surcharge, and account data.
Use a smaller box, right-size void fill, switch to mailers where safe, split or combine packages thoughtfully, and compare actual carrier rate tables.
Decision path
Use the moving box tool when total cubic feet and truck space matter more than parcel billing.
Convert unitsConvert centimeters, meters, kilograms, inches, feet, and pounds before entering carrier rules.
Storage volumeUse storage sizing when the same boxes are going into a unit instead of a parcel network.
