Concrete slab volume

Concrete Calculator

Calculate how much concrete you need in cubic feet and cubic yards from slab length, width and depth.

Concrete volume

Enter your measurements below. Results update automatically.

Length

Width

Depth

How this calculator works

Concrete is ordered by volume, not square footage, so slab thickness is essential. The calculator converts depth from inches to feet and then converts cubic feet to cubic yards.

FormulaCubic yards = length \u00d7 width \u00d7 (depth \u00f7 12) \u00f7 27

Worked example

A 10 \u00d7 10 ft slab at 4 in deep is about 1.23 cubic yards before adding contingency.

Useful answers

Concrete Calculator FAQs

How many cubic yards are in a 10 × 10 slab 4 inches thick?

About 1.23 cubic yards before adding any contingency.

How much extra concrete should I order?

A small contingency such as 5–10% is common, but the right amount depends on excavation accuracy and project shape.

Why can’t I calculate concrete from square feet alone?

Concrete has thickness, so you need a third dimension. Square feet describe area; concrete orders require volume.

How many cubic feet are in one cubic yard?

There are 27 cubic feet in one cubic yard.

Keep calculating

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