Concrete Calculator
Calculate the amount of concrete needed for slabs, square footings, walls, round footings, columns, circular slabs and tubes.
Slabs, Square Footings, or Walls
Enter length, width, thickness or height, and quantity. Each dimension can use a different unit.
Hole, Column, or Round Footings
Calculate cylindrical concrete volume from diameter, depth or height, and quantity.
Circular Slab or Tube
Calculate the volume of a circular slab or hollow tube using outer diameter, inner diameter, length or height, and quantity.
How To Use the Concrete Calculator
Choose the shape that matches your concrete project, enter the measurements and select the unit for each dimension. The result shows concrete volume in cubic feet, cubic yards and cubic meters, together with approximate premixed concrete weight and 60 lb and 80 lb bag quantities.
- Slabs, square footings and walls: use length × width × thickness/height × quantity.
- Holes, columns and round footings: use cylindrical volume from diameter and depth/height.
- Circular slabs or tubes: use the outer and inner diameters plus length/height.
- You can mix measurement units between fields.
Frequently Asked Questions (FAQs)
It calculates the volume of concrete required for the selected shape and quantity, then converts that volume into cubic feet, cubic yards and cubic meters.
This calculator supports slabs, square footings, walls, holes, columns, round footings, circular slabs and tubes.
Length dimensions can be entered in feet, inches, yards, meters or centimeters. Different fields may use different units.
The rectangular volume is calculated by multiplying length, width, thickness or height, and quantity after converting the dimensions to a common unit.
A round footing, hole or column is treated as a cylinder: π × radius² × height, multiplied by the quantity.
That is invalid for a hollow tube. The calculator stops the calculation and asks you to enter an inner diameter smaller than or equal to the outer diameter.
Yes. The result includes approximate 60 lb and 80 lb premixed bag counts based on the calculated concrete volume.
No. They are approximate estimates. Actual yield depends on the product, mix, moisture, site conditions and the manufacturer's stated coverage.