How to calculate CBM for multiple carton sizes

Measure each packed carton

CBM means cubic metres: the physical volume of your packed shipment. Measure the length, width and height of a closed carton on the outside, including packaging. For a rectangular carton that bulges, use the largest outside measurements.

Group cartons by identical dimensions and packed weight. Enter the dimensions of one carton and the number of cartons in that group. A different size belongs on another row.

The CBM calculator uses one dimension unit and one weight unit for the whole list. Convert measurements to that selected unit before combining rows. It accepts up to 100 carton-size rows.

Use the formula for your units

Total CBM = sum of (length × width × height × carton quantity), in metres

Multiply each row’s volume by its quantity once, then add the rows. The unit conversion factor applies to all three dimensions together. For example, 100 cm is 1 m, so a 100 × 100 × 100 cm box is 1 m³.

Add a mixed-carton shipment

This packing list has two carton sizes. Dimensions are in cm; packed weight is the weight of one complete carton.

0.96 + 0.225 = 1.185 m³

The shipment contains 15 cartons. Its packed weight is 10 × 12 + 5 × 8 = 160 kg. Volume and weight are separate totals; neither should be counted twice.

Download this example CSV

This is a worked packing list for reference. The current calculator exports CSV; it does not import a packing-list file.

Convert cubic feet and metres

A cubic foot and a cubic metre measure the same type of quantity. Using 1 ft = 0.3048 m, one cubic foot is 0.028316846592 m³. One cubic metre is approximately 35.315 cubic feet.

Our example shipment is 41.848 ft³. Keep the full measurements while doing the calculation and round the displayed total at the end. The calculator’s unit switch displays three decimal places; inspect converted inputs before using a tight fit or billing boundary.

Check the packing list

• Use outside packed dimensions, rather than the product size or the empty box’s inside dimensions.
• Keep the selected unit consistent across all rows.
• Enter a per-carton weight and a carton count, rather than entering a shipment total in every row.
• Measure a carton on a pallet separately from the complete pallet envelope. Do not count both as separate cargo.
• If weight is unknown, the tool accepts 0 and totals the weights entered. That is incomplete weight information, not proof of a weightless shipment.

Use the result in your next step

A CBM total does not tell you how many cartons physically fit on a pallet or in a container. Dimensions, orientations, doors, height and payload can prevent a load even when the summed volume is smaller than the space.

Use the pallet and container planner for a supported identical-carton layout. It cannot plan a mixed-carton load from this two-size example. For parcel billing, compare dimensions and actual weight in the DIM calculator under your service’s rules. CBM is not a transport quote and cannot be converted to kilograms without density or a clearly identified billing convention.

Sources and scope

Official references checked 4 October 2026. Numerical tables are worked planning examples using the stated inputs; they are not carrier prices or loading certification.

• DHL Express India: measuring a packed box ↗

  External dimensions of a closed, packed carton; the 40 × 30 × 20 cm / 5,000 worked example.

Read our calculation methods and limitations. To report an error or a changed official rule, contact Freight Layout.