Home Improvement

Concrete Calculator

Calculate how much concrete you need for your project.

Enter the length, width, and depth of your slab, footing, or driveway to calculate exactly how many cubic yards of concrete to order.

Enter a valid length.
Enter a valid width.
Enter a valid depth.

Concrete Needed

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Estimated Weight

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How to Use This Tool

  1. Measure the length and width of the area in feet.
  2. Enter the desired depth of concrete in inches.
  3. Click Calculate to see the volume needed in cubic yards.

The Volume Formula

Cubic Yards = (Length × Width × Depth in inches) ÷ 324

This formula converts your area (length × width, in square feet) and depth (in inches) into cubic yards — the standard unit concrete is sold by. The constant 324 comes from converting cubic feet to cubic yards (÷27) combined with converting inches to feet (÷12).

Common Slab Depths

Always Buy a Little Extra

Suppliers commonly recommend ordering 5-10% more than your calculated amount to account for settling, uneven ground, and spillage during placement.

Frequently Asked Questions

Why is concrete measured in cubic yards?

Cubic yards is the standard bulk measurement unit for concrete and similar bulk materials in the US, since it conveniently represents the volume typically delivered by truck.

Should I order extra material?

Yes, most suppliers and contractors recommend ordering 5-10% more than your calculated volume to account for uneven surfaces, settling, and waste during installation.

This calculator is provided for general informational and estimation purposes only. Results should not be treated as professional financial, tax, legal, medical, or engineering advice. Always verify critical calculations with a qualified professional or official source before making decisions.