How to estimate concrete
Multiply length by width by slab thickness in feet, then divide cubic feet by 27 for cubic yards.
Before you buy
Subgrade variation, footings, reinforcement, and delivery minimums can change your order. Structural work should follow local codes and engineering guidance.
Is this enough for a footing?
No. This calculator models a rectangular slab only; calculate footings separately.
Last reviewed: October 2026. This tool performs calculations locally in your browser.