Concrete Calculator

Use our free Concrete Calculator to quickly estimate the amount of concrete you need, based on key inputs like slab dimensions and thickness. Perfect for homeowners, builders, and contractors.

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Concrete Formula

Volume (cubic feet) = Length × Width × Thickness (in ÷ 12)\nVolume (cubic yards) = Volume (cubic feet) ÷ 27\nTotal Cost = Volume (cubic yards) × Cost per cubic yard
Example:
If your slab is 20 ft long, 10 ft wide, and 6 inches thick:\nVolume = 20 × 10 × (6 ÷ 12) = 100 cubic ft\nConvert to cubic yards: 100 ÷ 27 ≈ 3.7 cubic yards\nIf concrete costs $135 per cubic yard:\n3.7 × $135 = $500 (approx.)

Knowing how to calculate your concrete needs prevents costly over-ordering or under-ordering. Don't want to crunch the numbers? Use our free Concrete Calculator to get instant, accurate results.

How this concrete calculator works

This calculator estimates concrete volume by multiplying slab dimensions and thickness, then converting to cubic yards. It also multiplies by your local cost per cubic yard to provide a total project estimate.

When to use this concrete calculator

Planning a new driveway, patio, or walkway

Budgeting for foundation slabs or footings

Ordering the right amount of concrete from suppliers

Avoiding waste and unexpected overages

Comparing cost differences across slab sizes or mix types

Want to make your concrete projects smarter?

Use ServiceAgent.ai to automate estimates, manage proposals, and track profitability—all from one dashboard.

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Average Profit Margins by Industry

Understand how concrete and related construction services compare to other industries. Below are typical profit margin ranges across common service businesses:

Concrete Contractors

20–35%
net margin

Roofing Contractors

20–40%
net margin

HVAC Contractors

10–20%
net margin

Plumbing Contractors

20–35%
net margin

Electrical Contractors

15–25%
net margin

Cleaning Services

50–70%
net margin

Lawn Care

40–60%
net margin

General Construction/Contracting

15–30%
net margin

These benchmarks help contractors and homeowners assess whether project costs are competitive and profitable.

Frequently Asked Questions

It provides a close estimate. For best results, always round up to cover spillage and uneven subgrades.

Slab size, thickness, mix type, delivery charges, and local rates.

Yes—enter the correct dimensions to calculate the required volume.

Definitely. It provides fast, consistent estimates for project bids.

Yes—enter your local supplier's price for accurate results.

No—add those separately based on supplier charges.

Yes—most professionals recommend ordering 5–10% extra to account for waste.

Pair it with ServiceAgent.ai to automate quotes, proposals, and cost tracking.

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