Concrete Calculator
Estimate concrete volume and bag counts for a slab or footing from length, width, and depth, including a small waste allowance. DIY planning aid only.
Frequently asked questions
Why is there waste?
The estimate adds about 10% for spill, uneven ground, and overage. Buy a little extra rather than run short.
Is this a structural design?
No. It is a DIY volume estimate only — not engineering or building advice.