Concrete Calculator
Estimate the amount of concrete needed for a slab, footer, or column.
Planning a new patio, driveway, or foundation? Guessing how much concrete you need can be an expensive mistake. Order too little, and you face a "cold joint" and a ruined finish; order too much, and you're wasting money on disposal. Our Concrete Calculator helps you estimate the precise volume of concrete required in cubic yards and even converts it into the number of 80lb or 60lb bags you'll need for DIY projects.
Dimensions
Frequently Asked Questions
Working with Concrete
Concrete is sold by volume, typically in Cubic Yards. One cubic yard is equal to 27 cubic feet (imagine a box 3 feet wide, 3 feet long, and 3 feet deep). Calculating the exact volume is crucial for project budgeting.
1. Recommended Thickness
- 4 Inches: Standard for walkways, patios, and garage floors for cars.
- 5-6 Inches: Recommended for heavy duty driveways or areas with RV/Truck traffic.
2. The "Cure" Process
Concrete does not "dry" like paint; it cures via a chemical reaction called hydration.
- 24-48 Hours: Safe to walk on (carefully).
- 7 Days: Reaches ~70% of its potential strength. Vehicles can usually drive on new driveways.
- 28 Days: Considered fully cured and reaches its maximum design strength (e.g., 4000 psi).
3. Safety Warning
Wet concrete is highly alkaline (pH 12-13), similar to drain cleaner. It can cause severe chemical burns if left on skin for even a short time. Always wear waterproof gloves, boots, and long sleeves.