Concrete Material Calculator
How to Estimate Concrete
Calculating the amount of concrete needed for a project (slabs, footings, or walls) is essential to avoid shortages or over-ordering. Concrete is typically ordered by the cubic yard or purchased in pre-mixed bags.
The Concrete Formula
To find the volume, you multiply the three dimensions together. Since most measurements are taken in feet and inches, you must convert all units to feet before calculating.
Volume (Cubic Feet) = Length (ft) × Width (ft) × Depth (in) / 12
Once you have the cubic feet, divide by 27 to convert to cubic yards, as there are 27 cubic feet in one cubic yard.
Bagged Concrete vs. Ready-Mix
For small projects like walkways or fence posts, bagged concrete is convenient. One 80-pound bag yields approximately 0.60 cubic feet of concrete. One 60-pound bag yields approximately 0.45 cubic feet.
For larger projects (driveways, large slabs), ordering ready-mix concrete delivered by a truck is usually more cost-effective.