Building

Concrete Calculator

Estimate concrete volume for slabs, pads and rectangular pours in cubic yards and cubic metres.

✓ No signup✓ Mobile friendly✓ Clear limitations✓ Browser-first where practical
Recent tools are remembered only on this device.
Planning estimate. Verify final quantities, local codes, manufacturer instructions and site conditions before purchasing materials or carrying out work.
3.26Concrete cubic yards
2.49Concrete cubic metres
80Net volume ft³
4.56Approx. wet tonsDensity varies by mix

Why use this concrete calculator?

Concrete Calculator converts slab or pad dimensions into concrete volume and adds an adjustable waste allowance.

Example

Enter a 20 ft by 12 ft slab at 4 inches thick to estimate cubic yards before requesting a ready-mix quote.

Important note

Actual order quantity depends on excavation tolerances, subbase, formwork and supplier minimums. Verify site dimensions before ordering.

How to use it

Start with the inputs shown above, review the assumptions or options, then generate the result. Where the tool creates a file, keep the original until you have opened and checked the downloaded output.

Frequently asked questions

Is Concrete Calculator free?

Yes. The core tool is free to use without creating an account.

Do I need an account to use Concrete Calculator?

No. You can use the core Toolbox workflow without signing up.

Does Concrete Calculator work on mobile?

Yes. Toolbox is designed for modern mobile and desktop browsers, although complex file workflows can be easier on a larger screen.