Concrete Volume Calculator

Concrete volume calculator for slabs, footings, walls, and columns

This calculator estimates how much concrete you need based on your shape and dimensions. It is useful for common jobs like slabs and pads, strip footings, concrete walls, round columns, and circular pads.

Choose your units, pick the shape, and enter the measurements. The calculator returns the concrete volume in cubic meters (m³), litres, and cubic yards (yd³).

It also provides an ordering estimate that adds a waste allowance, which helps cover spillage, uneven excavation, formwork gaps, and over-excavation.

Assumptions and how to use this calculator

• All inputs are converted to meters internally before calculating volume.
• The ordering estimate adds a default waste allowance of 10% (common on many small-to-medium pours).
• Truck counts are estimates based on typical 6 m³ and 8 m³ loads. Your supplier may differ.
• This tool estimates volume only. It does not design reinforcement, mix strength, or structural details.

Common questions

How do I calculate concrete for a slab?

Select “Rectangular slab / pad” and enter length, width, and thickness. Thickness is usually the most commonly mistyped value, so double-check the unit you selected.

What thickness should I use?

This depends on the job and local standards. If you are unsure, use the thickness from your plan or builder and treat this calculator as a volume check, not a design tool.

Why add a waste allowance?

Concrete pours rarely match the perfect geometric shape. Waste allowance helps cover small losses and real-world variability so you do not run short mid-pour.

Should I order exactly the calculated volume?

Usually no. Ordering slightly more is common. This calculator shows both the exact volume and a 10% extra estimate so you can decide what is appropriate.

Does this include rebar, mesh, or formwork?

No. It calculates concrete volume only. Materials like reinforcement and formwork are separate quantities.