Calculate Concrete for Any Project
Whether you're pouring a patio slab, building footings, or constructing walls, accurate concrete calculations save money and prevent shortages. Our Concrete Calculator determines exactly how much concrete you need in cubic yards, bags, and provides cost estimates based on your project type.
Concrete Mix Types & Applications
Different projects require different concrete strengths:
| Mix Type | PSI Rating | Best For |
|---|---|---|
| Standard Mix | 2500-3000 PSI | Slabs, walkways, patios |
| High-Strength | 4000-5000 PSI | Driveways, foundations, heavy loads |
| Footing Mix | 3000 PSI | Foundation footings, posts |
| Counter Mix | 4000+ PSI | Countertops, decorative work |
Standard Concrete Thickness Guidelines
Required thickness varies by application:
| Application | Minimum Thickness | Recommended Thickness |
|---|---|---|
| Walkways | 3 inches | 4 inches |
| Patio Slabs | 4 inches | 4-6 inches |
| Driveways | 4 inches | 6 inches |
| Garage Floors | 6 inches | 6-8 inches |
| Foundation Walls | 8 inches | 10-12 inches |
Bags vs Ready-Mix: When to Use Each
Choose your delivery method based on project size:
Concrete Formulas by Shape
Volume calculations depend on the shape you're pouring:
Frequently Asked Questions
Q:How many 80lb bags of concrete equal 1 cubic yard?
It takes approximately 45 bags of 80lb concrete to make 1 cubic yard. For 60lb bags, you'll need about 60 bags per yard. This is why ready-mix is more economical for projects needing more than 1 yard.
Q:Should I add extra concrete beyond the calculated amount?
Yes, always add 5-10% waste factor. Ground is rarely perfectly level, forms may bow slightly, and some spillage is inevitable. It's cheaper to have extra concrete than to run short mid-pour and need an emergency delivery.
Q:How thick should a concrete slab be?
Standard thickness: 4 inches for walkways and patios, 6 inches for driveways and garage floors. Heavier loads (RVs, commercial use) require 8+ inches. Always check local building codes—some jurisdictions mandate minimum thicknesses.
Q:What's the difference between cubic feet and cubic yards?
Concrete is sold by the cubic yard, but calculations often use cubic feet. There are 27 cubic feet in 1 cubic yard (3 ft × 3 ft × 3 ft = 27). Always divide your cubic feet result by 27 to get yards for ordering.
Q:How much does a cubic yard of concrete cost?
Ready-mix concrete costs $125-$150 per cubic yard on average in 2026, with prices varying by region and mix strength. Add delivery fees ($50-$100), short-load fees for small orders (under 3 yards), and potential fuel surcharges. Always get quotes from multiple local suppliers.
Q:Can I pour concrete in cold weather?
Concrete can be poured in temperatures above 40°F (4°C), but special precautions are needed below 50°F. Use heated water for mixing, cover with insulated blankets, and consider accelerators. Never pour on frozen ground—it will cause cracking and failure.