ABNs verified. Licenses checked.
Toolbox / ConcretingConcreting · FREE CALCULATOR

Concrete volume & budget

Work out slab volume, an order allowance and your installed budget.

Quantity / scenario planning · Reviewed 7 October 2026

Your inputs

Check all starting values against your project and product. Enter your own prices; keep costs on the same GST basis.

MEASURE FIRST

How to prepare your inputs

Break the pour into non-overlapping shapes. Measure from approved plans, keeping millimetre thickness separate from metre dimensions.

How this calculation works

Volume = length × width × thickness ÷ 1,000. Order volume includes your waste allowance. Installed budget = net area × entered rate + extras.

Worked example

A 6 × 4 m slab at 100 mm is 2.4 m³. With 10% allowance, order volume is 2.64 m³.

Assumptions & exclusions

Use the thickness specified for your project. This tool does not design slabs or reinforcement. Installed rates should include supply and labour; do not add concrete supply again.

Your next step

Confirm the final pour schedule, access, delivery, reinforcement and placement with your concreter.

Further reading

  • Boral concrete planning

These resources provide background information. Confirm current product specifications and project requirements with your supplier or trade professional.

What if my shape or product is different?

Use dimensions and product data that match the stated method. For complex work, calculate separate sections or obtain a project-specific take-off. Do not apply simple geometry to structural or compliance decisions.

Why are quantities rounded up?

Whole bags, packs, sheets or cartridges round up to purchasable units. Decimal area or volume results are planning figures; confirm order increments with the supplier.

Are my entries saved?

No. Entries remain in the current browser page and clear on reload. Printing can save your results and inputs as a PDF on your device.

Keep planning

All Concreting tools →