Boneyard Tools

Dimensional Weight Calculator

Carriers bill the greater of a parcel's actual weight and its dimensional weight. Enter the box size, the scale weight and your carrier's dimensional divisor to see the cubic inches, the DIM weight and the billable weight.

How to calculate dimensional weight

  1. Enter the parcel length, width and height in inches.
  2. Enter the actual scale weight in pounds.
  3. Set the carrier dimensional divisor, commonly 139 or 166.
  4. Read the cubic inches, dimensional weight and billable weight.

Examples

Light bulky box (dimensional weight wins)

12 x 12 x 12 in, 5 lb actual, divisor 139
1728 cubic inches, DIM weight 12.4317 lb, billable 12.4317 lb

Same box on a 166 divisor

12 x 12 x 12 in, 5 lb actual, divisor 166
DIM weight 10.4096 lb, billable 10.4096 lb

Frequently asked questions

What is dimensional weight?

Dimensional weight, also called DIM weight or volumetric weight, prices a parcel by the space it occupies rather than how heavy it is. It equals the box volume in cubic inches divided by a carrier divisor. Carriers bill the larger of the actual scale weight and the dimensional weight.

Which dimensional divisor should I use?

It depends on the carrier and service. Many US domestic services use 139, while some retail or international services use 166. A smaller divisor produces a higher dimensional weight, so check your rate card or contract and enter the value it lists.

How is billable weight decided?

Billable weight is the greater of the actual weight and the dimensional weight. A small dense box is billed on its scale weight, while a large light box is billed on its dimensional weight, which can cost more than the scale suggests.

Do I round the dimensions before calculating?

Many carriers round each dimension up to the next whole inch before multiplying, then round the final dimensional weight up to the next pound. This tool multiplies the values you enter exactly, so round your inputs first if your carrier rounds dimensions.

Is my data stored?

No. The calculation runs entirely in your browser. Nothing you type is sent to a server or saved, so your dimensions and weights stay private on your device.

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