Overview
What Is a Concrete Calculator?
This tool calculates the volume of concrete (in cubic yards) needed for a slab, based on length, width, and thickness.
Calculate the volume of concrete needed for your project.
This tool calculates the volume of concrete (in cubic yards) needed for a slab, based on length, width, and thickness.
Useful for planning a concrete slab, walkway, or foundation project and estimating material needs.
Input the dimensions of your slab in feet.
Input the slab thickness in inches.
The result in cubic yards updates automatically.
Volume = Length × Width × Thickness, converted to cubic yards (1 cubic yard = 27 cubic feet).
Most professionals recommend ordering 5-10% extra to account for spillage, waste, and uneven subgrade.
4 inches is common for walkways and patios; 6 inches or more for driveways - check your local building code.
This calculates cubic yards for ready-mix - for bagged concrete, divide your cubic feet by the yield per bag (check your product label).
Break irregular shapes into rectangular sections, calculate each separately, and add the volumes together.
Yes, ready-mix concrete suppliers typically sell by the cubic yard.
No, this calculates concrete volume only - rebar and formwork are separate material considerations.
This varies significantly by region and supplier - contact local suppliers for current pricing.
No, calculations happen entirely in your browser.
Yes, completely free with no sign-up required.