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CBM calculator

Carton dimensions in, cubic metres out — plus the two weights a quote actually needs.
How many of this size.
Leave blank if you only need the volume.

How this is worked out

Cubic metres are length × width × height with every dimension converted to metres first. The conversion is where it goes wrong: a packing list in centimetres divided by 100 three times is the same as dividing by a million once, and a manifest that mixes centimetres from the factory with inches from the customer's ERP will quietly produce a figure sixteen times too small.

The volume alone is not the answer to anything. Air freight converts it to a weight on the 6000 divisor and bills the higher of that and the scale; ocean LCL converts it to a revenue ton — the higher of one cubic metre or one tonne — and bills that. The same box is light to a ship and heavy to an aircraft, so this page shows both rather than making you open two tabs.

Measure the outside of the carton, including any pallet the cargo sits on and any overhang past its edges. The carrier measures what physically occupies the space, not what the shipper meant to send.

A worked example

12 cartons at 60 × 40 × 45 cm, 18 kg each.
Each: 0.6 × 0.4 × 0.45 = 0.108 cbm. Twelve of them: 1.296 cbm.
Gross: 216 kg. Density: 216 ÷ 1.296 = 166.7 kg/cbm.
By air that is 216.0 kg volumetric against 216 kg actual — the exact tie. By sea it is 1.296 R/T, because the volume beats the 0.216 tonne.

What this does not do

Questions people actually ask

How do I calculate CBM from centimetres?

Multiply length × width × height in centimetres, then divide by 1,000,000. A 60 × 40 × 45 cm carton is 108,000 cm³, which is 0.108 cbm. Multiply by the number of cartons for the shipment total.

How many CBM fit in a 20ft container?

About 33 cbm on paper, and roughly 28 in practice — loose cartons stow at around 85% and palletised cargo closer to 75%, because pallets waste height and nothing stacks cleanly to the ceiling at the door. Quoting the theoretical figure is how a forwarder promises a load that does not fit.

Is CBM the same as chargeable weight?

No. CBM is a volume; chargeable weight is a weight the carrier derives from it. Air freight multiplies the volume by 166.7 on a 6000 divisor and bills whichever is higher, the derived weight or the scale. Ocean LCL turns the volume into revenue tons instead. The volume is the input to both, and the answer to neither.

Do I include the pallet in the measurement?

Yes, and the overhang too. The carrier measures the footprint the unit actually occupies — a 1.2 × 1.0 m pallet stacked 1.6 m high is 1.92 cbm even if the cartons on it only cube to 1.6, and any carton hanging over the edge sets the width. Measure the loaded pallet, not the cartons you put on it.

Related tools

Chargeable weight calculatorWhich weight the airline bills, and how much the volume adds. LCL vs FCL calculatorWhich is cheaper on your numbers, and the volume where that changes.
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