Concrete Calculator
Calculate the amount of concrete needed for a slab, column, or round footing. Get volume in cubic yards, cubic meters, and number of bags required.
Published by:
isCalculator Editorial Team
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How to use this tool?
Concrete Calculator – Quick Guide
- Select Shape: Choose Slab, Column, or Round Footing from the dropdown.
- Choose Unit: Pick Imperial (feet/inches) or Metric (meters/centimeters).
- Enter Dimensions:
- For Slab or Column: Input Length, Width, and Height/Thickness.
- For Round Footing: Input Diameter and Depth.
- Bag Size: Enter the weight of one concrete bag in pounds (default is 60 lbs).
- Calculate: Click the Calculate button.
- Read Results: The output shows:
- Total volume in cubic yards and cubic meters.
- Number of bags needed for your bag size.
Tip: All inputs must be positive numbers. Invalid entries will show red error messages.
Previous Results
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Frequently Asked Questions
Select the shape (slab, column, or round footing), choose your unit system (imperial or metric), enter the dimensions, and specify the bag size. Click Calculate to get the volume in cubic yards and cubic meters, and the number of bags needed.
Volume = Length × Width × Height (or thickness). For imperial, the result is in cubic feet, then converted to cubic yards (divide by 27) and cubic meters (multiply by 0.0283168).
The calculator assumes a standard 60 lb bag covers about 0.6 cubic feet. It divides the total volume in cubic feet by 0.6 and rounds up to the nearest whole bag.