Free online tool

Concrete Calculator

Enter slab dimensions and waste allowance to plan concrete volume and common bag counts.

Concrete to order-
Cubic feet-
Cubic meters-
40 lb bags-
60 lb bags-
80 lb bags-

Method

Project estimate method

Material quantities start with measured project dimensions, then apply the waste, coverage, or package values entered in the calculator.

Round purchase quantities up to the units actually sold and confirm product coverage, site conditions, dimensions, and local construction requirements before ordering.

Questions

Concrete Calculator FAQ

How much extra concrete should I order?

A 5 to 10 percent allowance is common for uneven subgrade, spillage, and measurement variation, but project conditions differ.

How many cubic feet are in a cubic yard?

One cubic yard equals exactly 27 cubic feet.

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