Construction

Concrete Calculator

Calculate the exact amount of concrete needed for slabs, footings, columns, walls, and tubes with bag and cost estimates

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Calculate Exactly How Much Concrete You Need

Planning a concrete project? Our concrete calculator helps you determine the precise amount of concrete needed for any shape—slabs, footings, columns, walls, or tubes. Get accurate volume estimates in cubic yards or meters, know how many bags you'll need, and see cost projections before you start.

How Concrete Calculations Work

Concrete is measured in cubic yards (US) or cubic meters (metric). The volume depends on the shape of your project. For slabs and footings, it's length × width × depth. For columns and tubes, we use π × radius² × height. Our calculator accounts for waste (typically 10%) and recommends whether to use bags or order ready-mix based on project size.

Volume Calculation Formula

V = L × W × D (slab) or V = π × r² × h (column)

How to Calculate Concrete Needed

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Common Use Cases

DIY Patios & Sidewalks

Calculate concrete for backyard patios, walkways, and garden paths.

Fence Post Footings

Determine concrete needed for post holes and fence foundations.

Foundation Work

Estimate concrete for footings, stem walls, and small foundations.

Contractor Estimates

Create accurate material quotes for concrete work and avoid over-ordering.

Frequently Asked Questions

It depends on the bag size: 80 lb bags yield about 0.6 cubic feet, 60 lb bags about 0.45 cubic feet, and 40 lb bags about 0.3 cubic feet. Our calculator shows all three options. For projects over 1 cubic yard, consider ready-mix delivery.