Concrete Calculator
Calculate concrete volume in cubic metres and number of bags needed.
You'll need
Pop in the slab size and we'll work out the volume.
How it works
Multiply length × width × depth (in metres) to get the volume in cubic metres. We add a waste percentage and convert to 25 kg bags using the standard yield of ~0.012 m³ per bag.
For larger pours, ready-mix concrete is delivered by volume directly to your site — quicker, stronger, and more economical than bags.