How to Use the Concrete Calculator

Calculating how many cubic yards of concrete to order can be difficult since we usually think in feet and inches and not yards. Also, areas to be filled with concrete are not always perfect rectangles. Often they are irregular shapes with angled sides,. Most areas to be filled with concrete can be divided into rectangles, triangles, and pier holes (circles or columns). The drawing at the bottom of this page shows a driveway, walkway, and stepping stone as an example. This calculator provides entries for each of these three main shapes. Each shape needs certain dimensions and a depth. You may enter your dimensions in feet, inches, or both feet and inches. The calculator computes the volume of each shape and converts it to cubic yards.

The calculator provides rows for you to enter the information for each of your shapes. Enter the dimensions in feet, inches, or both. When you select the calculate button, each area will have the cubic yards calculated and the totals for all areas will be shown at the bottom of the form.

Shapes:
Rectangles are defined by width, length, and depth
Triangles are defined by the length of each of the three sides (A, B, C) and depth
Pier holes (columns or circles) are defined by diameter and depth

Totals:
Cubic Yards = The number of cubic yards computed for the shape entered
Total Yards = The actual number of yards computed
Add for error = Apercentage to add (default 5%) to the total to allow for computational error and uneven excavation
Adjusted Yards = The Total Yards +computed error adjustment
Yards to order = Adjusted yards rounded up to next yard (Concrete is sold in whole yards.)

Buttons:
Calculate - Calculates Cubic Yards for each area and totals at the bottom
Clear - Clears all values including the "add for error" field
Help - Brings you to this screen

An example:
Let's assume that you have a driveway that is 9 feet wider at the street than at the garage door, a circular stepping stone between the driveway and a rectangular walkway. You subdivide the driveway to get one rectangle and two triangles. All the areas will be 4 inches deep.


Rectangle 1 Sidewalk
 29'    x   2' 6"          x 4"
Rectangle 2 Drive
 29'    x  17'             x 4"
Triangle 1 Drive
 29'    x   4' 5" x 29' 4" x 4"

Triangle 2 Drive

 29'    x   4' 5" x 29' 4" x 4"
Column Circle
  3' 6"                   x  4"

 

Concrete Ready Mix
Concrete Calculator

Rectangle 1
Width
Ft
In.
Length
Ft In.

 

Depth
Ft In.

Cubic Yards

Rectangle 2
Width
Ft
In
Length
Ft In
. Depth
Ft In.

Cubic Yards

Rectangle 3
Width
Ft
In
Length
Ft In.
  Depth
Ft In.
Cubic Yards
Rectangle 4
Width
Ft
In
Length
Ft In.
  Depth
Ft In.
Cubic Yards

Triangle 1

Side A
Ft
In
Side B
Ft In
Side C
Ft In.
Depth
Ft In.
Cubic Yards

Triangle 2

Side A
Ft
In
Side B
Ft In
Side C
Ft In.
Depth
Ft In.
Cubic Yards
Pier Hole 1
Diameter
Ft
In
 


Depth
Ft In.
Cubic Yards
Pier Hole 2 Diameter
Ft
In
 


Depth
Ft In.
Cubic Yards
Totals   Total Yards
Add for error
%
Adjusted Yards
Yards to Order