◧MeasureThenConstruction Calculators

Concrete Calculator

Calculate concrete volume, yards, and bags needed for any project.

How It Works

Volume (ft³) = Length × Width × (Thickness ÷ 12). Convert to cubic yards by dividing by 27.

Example

For a 10 ft × 10 ft pad at 4 in thick with 10% waste: 10 × 10 × (4 ÷ 12) = 33.3 ft³, × 1.1 = 36.7 ft³ ≈ 1.36 cubic yards (62 × 80 lb bags).

Frequently Asked Questions

What waste factor should I use?

A 5–10% waste factor is typical for slabs. Add more (10–15%) for footings or columns where forms and rebar cause extra waste.

How many bags are in a cubic yard?

Roughly 45 × 80 lb bags, 60 × 60 lb bags, or 90 × 40 lb bags fill one cubic yard.

Is concrete ordered by the cubic yard?

Yes. Ready-mix suppliers deliver by the cubic yard, so divide your volume in cubic feet by 27.

More Concrete Calculators

Concrete Slab CalculatorEstimate concrete and bags for a flat slab.Concrete Footing CalculatorCalculate concrete volume for wall and column footings.Concrete Column CalculatorEstimate concrete for round or square columns.Concrete Steps CalculatorCalculate concrete needed for steps and stairways.Concrete Bags CalculatorConvert concrete volume into the number of 40, 60, or 80 lb bags.Concrete Cost CalculatorEstimate the cost of concrete for your project.Concrete Yard CalculatorConvert concrete measurements into cubic yards.Brick CalculatorEstimate the number of bricks needed for a wall.Mulch CalculatorCalculate how much mulch you need in cubic yards.