How to calculate volumetric weight for freight in the real world

If you want to know how to calculate volumetric weight, start with the CTS volumetric weight calculator and then sanity check the result against how carriers actually price space. In practice, the key point is simple: a trailer fills up on cube long before it hits legal weight on many consignments, and airlines are even stricter. That is why the industry prices on whichever figure bites first.

What the CTS volumetric weight calculator does and who it is for

The CTS tool is built for people who have to price freight properly, whether you are shipping a few pallets a week or tendering regular lanes. You enter length, width and height in centimetres, weight in kilograms, and quantity for each item line. You can add as many lines as you need, then select road, air or sea. The calculator totals volume in cubic metres, converts that volume into a volumetric weight using the relevant factor, and shows the chargeable weight alongside your actual weight. There is a PDF download and no sign up, which suits quick checks before you book or quote.

It also shows loading metres for road work, based on deck floor area divided by 2.4 metres, the standard trailer width. That matters on dense traffic where floor space is the constraint. If you outsource your transport through CTS managed freight services, these are the same mechanics used to sense check rates and pick the right operator for the job.

Industry standard density factors used by UK carriers

Volume is calculated as length times width times height times quantity for each row, expressed in cubic metres. Volumetric weight is that volume multiplied by a mode specific density factor. Chargeable weight is the greater of actual and volumetric weight, because vehicles and aircraft run out of space as surely as they run out of payload.

For road freight, a common European groupage standard is 333 kilograms per cubic metre, effectively a one to three relationship between tonnes and cube, although some carriers apply 250 or 280. Air freight uses 167 kilograms per cubic metre, derived from the IATA divisor of 6000 cubic centimetres. Sea LCL is priced as a revenue tonne, also called weight or measure, where one cubic metre equals one tonne, or 1000 kilograms.

Those figures are widely used, but individual carriers can set their own ratios, so treat any calculation as a strong estimate and confirm against the rate card. Actual weight still has to sit within vehicle payload and gross limits, which are set out in the official vehicle weights explained guidance. Get both sides right and you avoid nasty surprises at invoicing.

How to calculate volumetric weight with the CTS tool

1. Enter the length, width and height of each item in centimetres.
2. Add the weight of each item in kilograms, then enter the quantity.
3. Create another item line for any freight with different dimensions or weight.
4. Select road, air or sea freight and run the calculation.
5. Review the actual weight, volumetric weight, chargeable weight and any road loading metres shown.
6. Download the PDF if you need a record for buying or checking a booking.

Measure the packed freight, not the bare product. Cartons, pallets, stillages and protective packing all take up space. Keep each size on its own line rather than averaging mixed pieces, because an average can hide a bulky item. Weight each piece where possible and use the total quantity for identical units. Small errors repeated across a quantity can change the chargeable weight and the price.

Reading the result and using it properly

Start with the chargeable weight. It is whichever is greater, the shipment's actual weight or its volumetric weight. That is the figure most likely to drive the freight charge, since carriers can fill the available deck or aircraft space before reaching the payload limit.

The calculator applies the standard factors covered earlier for road, air and sea, so the number you see should line up with most rate cards. The exception is road groupage, where some carriers price at 250 or 280 kg per cubic metre rather than 333, so check the operator's own ratio before treating the result as final.

Road results also include loading metres. The figure is based on total deck floor area divided by 2.4, the width in metres of a standard trailer deck. It is useful where freight occupies floor space that cannot be shared, but it does not replace a discussion about stackability, access, overhang or restraint.

Treat the output as a strong buying estimate, then confirm the carrier's own ratio and charging basis. Keep actual weight in view as a separate operational limit, because vehicle payload and gross weight rules still apply even where volumetric weight sets the price. The GOV.UK vehicle weights explained material is the right place to check those legal limits.

Use the CTS volumetric weight calculator before you ask the market for a rate. For firm prices from suitable transport companies, request freight quotes through CTS with the dimensions, weights, quantities and mode ready.

Frequently asked questions

How do I calculate volumetric weight for road freight in the UK?

Work out the volume as length x width x height x quantity in cubic metres, then multiply by 333 kg per cubic metre. Compare that figure with the actual weight and use the greater value as the chargeable weight.

What divisor is used for air freight volumetric weight?

Air freight uses a divisor of 6,000 cubic centimetres, which is equivalent to 167 kg per cubic metre. The chargeable weight is whichever is higher, the actual weight or the volumetric weight.

How is sea LCL charged under weight or measure?

Sea LCL is charged as a revenue tonne, taking the greater of the shipment’s cubic metres or its weight in tonnes. This is equivalent to 1,000 kg per cubic metre when comparing volume and weight.