Dimensional Weight Calculator
This dimensional weight calculator finds the volumetric weight carriers use to price a shipment, then compares it to the actual weight to show the chargeable weight. Enter the box size and weight and the dimensional weight calculator does the calculation of dimensional weight for you, so you know what you will be billed before you ship.
Results
The Dimensional Weight Calculator is part of our Shipping collection. Browse more shipping to size, convert, and check your work alongside this tool.
What the dimensional weight calculator does
The dimensional weight calculator works out the volumetric weight that shipping companies use when a package is bulky but light. Carriers charge on whichever is greater, the actual weight or the volumetric weight, so this dim weight calculator shows both and picks the chargeable weight. Running the calculation of dimensional weight before you ship stops billing surprises.
Dim weight formula
The dimensional weight calculator multiplies the three dimensions and divides by the DIM divisor:
With centimeters and a divisor of 5000, the dim weight formula gives kilograms. The calculator then compares the volumetric weight to the actual weight and reports the higher one as the chargeable weight.
Dimensional weight calculator example
A 60 × 40 × 50 cm box at a 5000 divisor, run through the calculation of dimensional weight:
If the actual weight is only 15 kg, the dim weight of 24 kg becomes the chargeable weight, because the volumetric weight is higher.
How to use the dimensional weight calculator
Enter the box length, width, and height in centimeters, the carrier's dimensional divisor, and the actual weight. The dimensional weight calculator returns the volumetric weight and the chargeable weight. Different couriers use different divisors, so set the one your carrier uses for an accurate calculate volume weight result.
Reading the dimensional weight result
When the volumetric weight beats the actual weight, your box is bulky for its weight and you pay on volume. The dimensional weight calculator makes this visible so you can repack into a smaller box and cut the chargeable weight. When actual weight wins, the package is dense and volumetric weight does not apply.
When to use the dimensional weight calculator
- Estimating courier costs by calculating volume weight before you ship
- Comparing carriers by their dimensional divisor
- Deciding whether to repack to lower the chargeable weight
- Checking an invoice against your own calculation of dimensional weight
Common dimensional weight mistakes
- Wrong divisor. Using 6000 when your carrier uses 5000 understates the volumetric weight.
- Measuring the contents, not the box. The dimensional weight calculator needs the outer carton size.
- Ignoring volumetric weight. A light, bulky box is billed on volume, not the scale.
Tips for accurate dimensional weight results
- Use your carrier's exact divisor in the dimensional weight calculator.
- Measure the outer box at its widest points, rounding up.
- Repack bulky items to lower the chargeable weight.
Why carriers use a dimensional weight calculator
Aircraft and trucks run out of space before they run out of weight capacity, which is the whole reason volumetric weight exists. A van filled with pillows hits its volume limit while barely loaded by weight, so charging by actual weight alone would lose the carrier money. The calculation of dimensional weight prices the space a package occupies, and the dimensional weight calculator lets you see your shipment the way the carrier does, as a claim on scarce cubic capacity.
Cutting the chargeable weight
Once the dimensional weight calculator shows volumetric weight winning, you have a lever. Repacking into a snugger box lowers the dim weight directly, sometimes dropping you into a cheaper bracket. Removing excess void fill, choosing a box that fits the contents, and flattening irregular shapes all reduce the volumetric weight. Running the calculate volume weight step on a few box options before shipping is one of the simplest ways to trim recurring freight costs.
Dimensional divisor chart
Common divisors used in the calculation of dimensional weight:
| Carrier type | Divisor (cm/kg) |
|---|---|
| International air | 5000 |
| Domestic express | 4000–5000 |
| Some couriers | 6000 |
Dimensional Weight Calculator FAQ
How do I calculate dimensional weight in cm and kg?
Multiply length × width × height in centimeters and divide by the carrier divisor, usually 5,000 for express (some use 6,000). A 60 × 40 × 50 cm box gives 120,000 ÷ 5,000 = 24 kg, or 52.91 lb. In inches and pounds, divide by 139 instead.
What is volumetric weight?
Volumetric weight, or dim weight, prices the space a package occupies rather than its mass. The dimensional weight calculator finds it so bulky, light boxes are billed fairly by volume.
Which weight am I charged?
The chargeable weight, which is the greater of actual and volumetric weight. The dim weight calculator highlights whichever one you will be billed for.
What is the dim weight formula?
Length times width times height, divided by the dimensional divisor. That dim weight formula, with dimensions in centimeters and a divisor like 5000, is what the calculator applies.