Cubic weight calculator: actual or dimensional?
Enter your item dimensions and find out which weight your freight will be charged on — and how much of a trailer your cargo takes up. The maths is the same at any carrier, and the factor is editable.
Work out your shipment.
Enter the items in your shipment
Cubic weight comes from a simple calculation: length × width × height, in metres, gives the volume in m³. Multiplied by the carrier’s dimensional factor (300 kg/m³ is the most common in Brazilian road freight), that volume becomes the cubic weight. Freight is charged on the greater of cubic weight and actual weight.
The interactive form on this page requires JavaScript. The formula above gets you to the same number by hand.
Diesel is the largest variable cost of any road trip. Follow the national average, alongside the exchange rate and fuel inflation, on Diesel hoje (in Portuguese).
Why cubic weight exists.
A truck runs out of space long before it runs out of payload. A trailer takes roughly 27 tonnes but only 90 cubic metres — anyone shipping cushions, packaging or plastic parts fills the whole trailer without coming close to the axle limit.
If freight were charged on scale weight alone, that cargo would travel almost free and the bill would fall on whoever ships dense goods. Cubic weight corrects this: it converts occupied space into equivalent kilos, and billing uses the greater of the two. Dense cargo pays actual weight; bulky cargo pays cubic.
That is why the same shipment can carry two “weights” on a quote without anyone being wrong — they are two different measurements of the same truck.
How the number is reached.
1. Measure each item in centimetres
Length, width and height of the packed item — including the pallet, if it travels palletised. What counts is the space the cargo occupies in the truck, not the bare product dimension.
2. Convert to cubic metres
Divide each measurement by 100 and multiply the three. An item of 120 × 80 × 100 cm gives 1.2 × 0.8 × 1.0 = 0.96 m³. Multiply by the number of identical items.
3. Apply the dimensional factor
Multiply total m³ by the carrier’s factor. At the 300 kg/m³ standard, those 0.96 m³ become 288 kg of cubic weight. If the item weighs less than that on the scale, cubic weight is what counts.
4. Compare with actual weight
Freight takes the greater of the two. The calculator above makes that comparison and also estimates how much of the trailer the shipment consumes — usually the deciding factor between LTL and a dedicated vehicle.
Questions about cubic weight.
What are cubage and cubic weight?
Cubage is the volume the cargo occupies, in cubic metres: length × width × height. Cubic weight is that volume multiplied by the carrier’s dimensional factor. It exists because a truck fills up on space before it fills up on weight — light, bulky cargo consumes the whole trailer without coming close to the axle limit.
Why is freight charged on cubic weight instead of actual weight?
It is not always. The rule is to charge on whichever is greater. If the cargo is dense (steel, liquid, paper), actual weight wins. If it is bulky (foam, packaging, plastic), cubic weight wins. The calculator on this page shows which one prevails for your shipment.
Which dimensional factor should I use?
Whichever appears on your quote. In Brazilian road freight 300 kg/m³ is the most widely used, and it is pre-filled here — but 250 and 333 also circulate, because the factor is each carrier’s commercial term, not a regulation. That is why the field is editable.
How do I know whether LTL or full truckload suits my shipment?
By how much of the trailer it uses. The calculator estimates that share, taking whichever is more limiting between volume and weight. Below roughly half a trailer, LTL usually pays off: you pay for the space you use. Close to filling the vehicle, full truckload tends to be better.
Does this calculator work for any carrier?
Yes — the maths is the same across the market, and the factor is editable precisely so you can use the one from your quote. One clarification: MAC Transportes does not use cubic weight. In full truckload the vehicle is dedicated to your cargo and pricing is built per trip and route; in LTL we charge by actual weight and the space used. So the most useful output on this page, for anyone quoting with us, is the trailer occupancy — that is what points to the right service.
Want us to check that number?
Send us the product, dimensions, weight, origin and destination. We will quote it and tell you honestly whether LTL or a dedicated trailer works out better.
See also
Who maintains this page Tool maintained by MAC Transportes, a road freight carrier based in Lagarto, Sergipe, Brazil, with RNTRC no. 049072622, active at ANTT, its own cargo insurance policy and CT-e and MDF-e issuance. The cubage calculation shown here is the one used across Brazilian road freight; the factor is editable because each carrier sets its own. The result is a reference estimate and does not replace a formal quote. The operation is run by partners Carlos Alberto and Viviane, who are responsible for the day-to-day of the carrier.