Dimensional Weight Calculator
Find dimensional and billable shipping weight.
Carrier factor (139 for domestic in³/lb). Defaults to 139.
Optional. Billable weight is the greater of actual and dimensional.
Results update as you type.
How it works
Dimensional weight, often shortened to DIM weight, is how modern carriers charge for the space a package takes up instead of just how heavy it is. This dimensional weight calculator multiplies length, width, and height, divides by the carrier's DIM divisor, and returns the volumetric weight along with the billable weight you will actually pay for. Because trucks and aircraft run out of room before they run out of payload, a large but lightweight box can cost far more to ship than its scale weight suggests. Understanding DIM weight matters for anyone shipping products, from ecommerce sellers pricing fulfilment to warehouse teams negotiating carrier contracts. Enter your dimensions in inches and the divisor your carrier uses, and the tool shows whether the parcel is billed on actual or dimensional weight, which is always the higher of the two. The calculation works because the DIM divisor encodes an assumed density: a divisor of 139 treats every 139 cubic inches as one pound. Add your real package weight and the calculator picks the billable figure automatically, so you can right-size boxes, cut void fill, and forecast freight costs before a shipment ever leaves the dock or a label is printed.
DIM weight = (length × width × height) ÷ divisor
Dimensional weight prices the space a parcel occupies rather than its mass, so multiplying the three dimensions gives cubic volume and dividing by the carrier's DIM divisor converts that volume into an equivalent weight. The formula works because a truck or plane fills its cube long before it hits its weight limit, so carriers bill the greater of actual and dimensional weight to recover the value of the room a light, bulky box consumes.
Source:Standard freight/logistics formula
We review all our tools from time to time to ensure accuracy.
Worked example
How to use this calculator
- 1
Enter your values
Enter length, width and height.
- 2
Adjust the options
Adjust dim divisor and actual weight if they apply — sensible defaults are already set.
- 3
Read your result
Dimensional weight updates instantly as you type — no button to press.
Frequently asked questions
What is a DIM divisor and which one do I use?
A DIM divisor converts cubic size into a weight by assuming a standard density. Common domestic divisors are 139 for inches and pounds, though carriers use 138, 166, or metric equivalents depending on the service and contract. Always confirm the exact divisor in your carrier agreement, because a smaller divisor produces a larger dimensional weight and a higher shipping charge for the same box.
How is billable weight decided?
Billable weight is simply the greater of a parcel's actual scale weight and its dimensional weight. Carriers compare the two and charge whichever is higher, so a heavy, compact box bills on actual weight while a light, bulky box bills on dimensional weight. Entering your real weight lets this calculator flag which figure applies, helping you avoid surprises when the freight invoice arrives.
Why do carriers charge by dimensional weight?
Delivery vehicles and aircraft fill their available cubic space long before they reach their maximum payload. If carriers billed only by mass, a trailer packed with light, oversized boxes would earn far less than its capacity is worth. Dimensional weight recovers the value of that occupied space, encouraging shippers to use right-sized packaging and reduce wasted volume across the entire distribution network.
Can I reduce my dimensional weight?
Yes. Because dimensional weight depends only on the box size, shrinking any dimension lowers it. Use packaging that fits the product closely, remove excess void fill, and avoid oversized cartons for small items. Even trimming a couple of inches from the longest side can drop a parcel into a lower billing tier, so testing tighter box sizes is one of the fastest ways to cut shipping spend.
Does dimensional weight apply to freight and pallets too?
Parcel carriers rely most heavily on dimensional weight, but less-than-truckload freight uses a related concept called density to assign freight class. Pallets and large shipments are rated on weight, dimensions, and how efficiently they fill space. The principle is the same: space costs money. For pallet shipments, pairing this tool with a freight density calculator gives a fuller picture of your costs.