Concrete Calculator
Calculate cubic yards, cubic meters, and bags needed for your concrete project
Did you know that concrete continues to get stronger for years after it's poured?
Select Shape:
Slab/Footing Dimensions:
Column Dimensions:
Stairs Dimensions:
Options:
Recommended: 5-10% for slabs, 10-15% for complex shapes
How to Use the Concrete Calculator
This calculator helps you determine how much concrete you need for various construction projects. Calculate cubic yards, cubic meters, and the number of concrete bags required for slabs, footings, columns, and stairs.
Select Your Shape
Slab/Footing: For driveways, patios, floors, walkways, foundation footings, and trenches. Enter length, width, and thickness/depth.
Column: For round columns, piers, and sono-tubes. Enter diameter and height.
Stairs: For outdoor steps and staircases. Enter width, number of steps, tread depth, and rise height.
Understanding the Results
Cubic Yards: The standard measurement for ordering ready-mix concrete in the US. Most concrete trucks deliver in cubic yard increments.
Cubic Meters: The metric measurement for concrete volume, commonly used internationally.
Cubic Feet: Total volume in cubic feet (1 cubic yard = 27 cubic feet).
60 lb Bags: Each 60-pound bag yields approximately 0.45 cubic feet of concrete.
80 lb Bags: Each 80-pound bag yields approximately 0.60 cubic feet of concrete.
Waste Factor
Always add extra concrete to account for spillage, uneven ground, and over-excavation:
- 5-10%: Simple rectangular slabs on level ground
- 10-15%: Footings, columns, and irregular shapes
- 15-20%: Complex projects or uneven terrain
Common Concrete Depths
- 4 inches: Walkways, patios, light-duty residential slabs
- 6 inches: Driveways, garage floors, heavy-duty slabs
- 8 inches: Heavy vehicle traffic, commercial applications
- 12 inches: Foundation footings (varies by local code)
Bags vs. Ready-Mix
Use bags for: Small projects under 1 cubic yard, repairs, or when mixing by hand.
Use ready-mix for: Projects over 1 cubic yard. Ready-mix is more cost-effective for larger jobs and provides more consistent quality.
Tips for Success
- Measure your project area carefully before ordering
- Check local building codes for required depths and specifications
- Consider weather conditions - concrete sets differently in hot vs. cold weather
- Have all tools and helpers ready before concrete arrives
- Don't add water to ready-mix to make it easier to work - this weakens the concrete