PACKING LIST / CUBIC METRES
How to calculate CBM for a shipment
CBM (cubic metres) is the space your packed cartons take. The arithmetic is one multiplication per carton size; the work is in measuring the right thing and not rounding too early. A real-looking packing list shows how much each mistake costs.
Updated 28 October 2026 · figures from the linked sources or computed by the Livnaro calculator with the inputs shown
The calculation
CBM per carton = length × width × height (m)
Line CBM = CBM per carton × cartons · Shipment CBM = sum of the lines
In centimetres divide the product by 1,000,000; in millimetres by 1,000,000,000; in inches by 61,023.74. Keep one line per carton size. Averaging the sizes of different cartons gives a wrong total, because volume does not average linearly.
A five-line packing list
A home-goods order for one container, entered in the CBM calculator:
| Item | L × W × H | Cartons | m³ per carton | Line m³ |
|---|---|---|---|---|
| Desk lamp | 52 × 38 × 44 | 120 | 0.086944 | 10.433 |
| Side table, flat-pack | 86 × 52 × 14 | 200 | 0.062608 | 12.522 |
| Ceramic planter set | 46 × 46 × 40 | 150 | 0.084640 | 12.696 |
| Rug roll | 160 × 28 × 28 | 80 | 0.125440 | 10.035 |
| Storage box | 60 × 40 × 36 | 200 | 0.086400 | 17.280 |
| Total | 750 | 62.966 |
The measuring error that costs a container
Measure the packed carton at its widest points: tape, labels, bulging lids and handles all travel. Now suppose every carton in the list is 1 cm larger on each side than the factory drawing says.
- Small cartons grow most: the flat-pack table (14 cm high) gains 10.5%, the others 7.0–7.9%.
- The shipment goes from 62.966 m³ to 67.920 m³, +7.9%.
- At 85% fill a 40' HQ has 64.9 m³ of usable volume. The drawing figures fit one; the real cartons need two.
The fix costs nothing: measure one packed carton of each size before the booking, and give the forwarder those figures.
Round the total, not the cartons
Rounding each carton to 0.01 m³ before multiplying turns the same list into 63.20 m³ (+0.37%); to 0.001 m³ gives 62.99 m³. Small on one line, but per-carton rounding is where lists disagree with the forwarder's figure. Keep at least four decimals per carton, as the worksheet and its CSV export do.
After the CBM
The total decides LCL versus FCL and which charge rule applies. Compare the modes in CBM to kg, check pallets in how many pallets fit, and when the order turns into a quote, Livnaro's Quotepad proforma invoice generator carries the carton list into the paperwork.
Keep going
Guides
- CBM to cubic feet (and back)1 CBM = 35.3147 cubic feet because 1 ft is exactly 0.3048 m.
- CBM to kg: the conversion carriers useThere is no physical CBM to kg conversion.
- Container loading calculator: what a free tool can answerWhat a free container loading calculator can work out (volume fill, turned-carton counts with drawings, pallet floor positions, weight, mixed container sizes) and what still needs a load plan.