How the volume calculation works
Volume = length × width × depth.
Worked example
A 5 m × 4 m × 0.2 m rectangular space has a volume of 4 m³, which equals 4,000 litres.
Guide: using this calculator accurately
For the full explanation, worked examples, measurement tips and FAQs, read the Volume Guide →.
How volume differs from area
Area measures a surface, while volume measures three-dimensional space. Adding a depth or height to an area calculation turns it into a volume.
Keep all three dimensions in the same unit
For cubic metres, enter all dimensions in metres. Convert centimetres or millimetres before multiplying.
Where volume is useful
Volume calculations are common for concrete, soil, mulch, gravel, water tanks and rectangular containers.
Volume and material weight are different
A cubic metre does not have one fixed weight. If you need tonnes or kilograms, use the appropriate material density supplied for the product.
Common volume mistakes
A depth of 20 cm is 0.2 m, not 20 m. Unit conversion is the most common source of large errors.
Frequently asked questions
How many litres are in one cubic metre?
One cubic metre equals 1,000 litres.
Can I calculate a trench?
Yes, if the trench can be reasonably represented by a rectangular section. For changing widths or depths, split it into sections.
Can volume tell me how many tonnes I need?
Only if you also have a suitable material density. Different materials and moisture conditions can have different densities.