Concrete Cost Estimator
Enter your slab dimensions and local ready-mix price to get cubic yards needed and a full project cost, including labor, delivery, and rebar.
Get this from a local ready-mix supplier quote.
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Concrete Cost Estimator
A typical concrete slab costs $4 to $8 per square foot installed, or roughly $110 to $165 per cubic yard for ready-mix material alone. Enter your slab dimensions and local price per yard above for a project-specific estimate.
How the cost is calculated
- Measure the slab: 20 ft long by 10 ft wide by 4 in thick.
- Convert thickness to feet: 4 ÷ 12 = 0.33 ft.
- Find the volume: 20 × 10 × 0.33 = 66.7 ft³.
- Convert to cubic yards: 66.7 ÷ 27 = 2.47 yd³.
- Add a 10% waste allowance: 2.47 × 1.10 = 2.72 yd³.
- Multiply by the delivered price: 2.72 × $150 = $408 in material.
- Add labor, delivery, and rebar for the full project total.
Worked example
A 20 ft by 10 ft patio slab poured 4 inches thick needs about 2.72 cubic yards of concrete after a 10% waste allowance. At $150 per yard, that’s roughly $408 in material. Add $600 for labor and finishing (at $3/ft²), a $125 delivery fee, and $80 for wire mesh, and the full project runs about $1,213 — or roughly $6 per square foot.
Assumptions this estimate makes
- Slab thickness is assumed uniform across the entire pour area.
- Price per yard reflects a delivered ready-mix quote from a local supplier, not a bagged-concrete price.
- The waste factor defaults to 10% and can be adjusted for site conditions.
- Labor, delivery, and rebar are optional add-ons and are excluded unless toggled on.
Common mistakes to avoid
- Forgetting to add a waste allowance and ending up with a short load on pour day.
- Using bagged-concrete pricing to estimate a large ready-mix pour, which overstates the cost.
- Not confirming minimum order or short-load fees with the supplier before ordering.
- Leaving rebar or wire mesh out of the budget entirely.
Frequently asked questions
How much does a concrete slab cost per square foot?
Ready-mix concrete typically runs $4 to $8 per square foot installed for a basic 4-inch slab, though labor, thickness, reinforcement, and site prep can push the price higher.
How many cubic yards of concrete do I need for my project?
Multiply length by width by thickness in feet, divide by 27 to get cubic yards, then add 5 to 10 percent for waste and spillage.
Why should I add a waste percentage to my order?
Concrete gets lost to uneven subgrade, spillage, and minor spec deviations, so ordering extra avoids a costly second short-load delivery.
What extra costs come with a concrete pour besides material?
Labor and finishing, delivery or pump fees, rebar or wire mesh, and site prep like grading or forming can each add to the total.
Is it cheaper to buy bagged concrete or order ready-mix?
Bagged concrete usually costs more per cubic yard than ready-mix delivery once a project passes about 1 to 2 cubic yards, so ready-mix is typically cheaper for slabs, driveways, and patios.