Cubic Metre Calculator

This calculator works out the volume of a box-shaped item or space in cubic metres (CBM), the standard unit used for shipping, freight, storage and materials like concrete or mulch. Enter the length, width and height, choose whether you measured in centimetres or metres, and add a quantity if you have several identical boxes or cartons. It instantly returns the volume per item and the total volume for your full quantity, both shown in cubic metres. Behind the scenes it multiplies length by width by height, then divides by 1,000,000 if you entered centimetres, since there are a million cubic centimetres in a cubic metre. This is particularly useful for freight and shipping, because carriers price sea and air cargo partly on CBM, and a standard 20 foot container holds roughly 33 cubic metres of usable space, so knowing your total volume helps you estimate cost and how much will fit. It is equally handy for concrete pours, garden beds, storage units, or any other rectangular volume around the house or jobsite. If you have several different box sizes, work out each size separately and add the totals together, since it handles one size at a time. Double check your units before reading the result, and remember real-world packing rarely fills every cubic metre efficiently, so allow some margin when planning freight or storage space.

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0.96 m³
total volume
Per item0.96 m³
Quantity1

How to calculate cubic metres

Multiply length by width by height, with all three measurements in metres. If you measured in centimetres, multiply the three numbers and divide by 1,000,000, because one cubic metre contains 1,000,000 cubic centimetres. For several identical items, multiply the volume of one by the quantity.

Worked example

A carton measures 120 cm long, 80 cm wide, and 100 cm high. Multiplying gives 960,000 cubic centimetres. Divide by 1,000,000 to get 0.96 cubic metres per carton.

If you are shipping 10 of these cartons, the total is 9.6 cubic metres, which helps you estimate freight cost and how many fit in a container.

What CBM means for freight

CBM (cubic metre) is how carriers measure volume for sea and air freight. Freight is often charged on whichever is greater, the actual weight or the volumetric weight, so knowing your CBM helps you compare quotes and plan loads. A standard 20 foot shipping container holds roughly 33 cubic metres of usable space.

Frequently asked questions

How many cubic centimetres are in a cubic metre?

One million. That is why you divide a measurement in cubic centimetres by 1,000,000 to get cubic metres.

How do I get total CBM for mixed box sizes?

Work out each box size separately, then add the totals together. This calculator handles one box size at a time with a quantity.

Who this calculator is for

This calculator is for anyone working out a volume in cubic metres, for shipping, concrete, storage or landscaping.

What this calculator assumes

  • The dimensions and units you enter.
  • A rectangular (length by width by height) volume unless stated otherwise.
  • All dimensions are in consistent units.
  • Add a wastage allowance when ordering materials.

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