Concrete Cost Calculator

A poured, finished concrete slab runs about $5 to $9 per square foot for a standard gray, broom-finished slab, including labor. Colored or exposed-aggregate work runs $8 to $14, and stamped or decorative concrete runs $12 to $22. The calculator above prices your slab by size and finish. Site prep, tear-out of an old slab, rebar or wire mesh, and the local labor rate all move the number, which is why the on-site quote is the firm one.

Concrete is ordered by the cubic yard. Multiply the slab area in square feet by the thickness in feet, then divide by 27 to get cubic yards, and add about 10 percent for waste and over-order. A 20 by 20 foot slab at 4 inches thick works out to roughly 4.9 cubic yards with the waste allowance. The calculator does this math for you and shows the volume alongside the cost.

Four inches is standard for a patio, walkway, or shed floor. A driveway that carries vehicles is usually poured at 5 to 6 inches, and anything holding heavy equipment goes thicker. Thickness drives how much concrete you buy, so it moves the material cost directly. Set the thickness in the calculator to match your job.

The base per-foot range covers the pour and finish. It usually does not cover tearing out and hauling away an old slab, major grading or fill, a thicker sub-base, rebar on a heavy-load pour, or decorative sealing on a standard job. On a sloped or hard-to-reach site, getting the truck and the concrete to the forms adds labor. These are the items that separate a rough estimate from the on-site quote.

A standard concrete slab is usually cheaper up front than a paver patio of the same size, because pavers are labor-heavy to lay. Stamped decorative concrete closes that gap and can cost about the same as mid-grade pavers. Pavers are easier to repair in one spot and concrete is faster to install, so the choice is about look and long-term upkeep as much as price.