Concrete Driveway Calculator
A standard two-car driveway (20×50 ft at 5 inches thick) needs 15.4 cubic yards of concrete — that's one ready-mix truck. Enter your dimensions below for the exact volume, bag count, and cost estimate.
Pro Tips
- →Driveways should be 5-6 inches thick for passenger vehicles
- →Add 10% extra for waste and uneven ground
- →Consider 6-8 inches for heavy vehicles like RVs or trucks
- →A two-car driveway is typically 20 feet wide
- →Allow concrete to cure for 7 days before driving on it
Includes 10% waste factor
That's typically a professional pour. See costs ↓
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Cost Estimate
Estimated material costs for your project
Recommendation: Ready-Mix Concrete
For projects over 1 cubic yard, ready-mix is typically more economical and easier to work with.
764 bags × 80lb
16.98 cubic yards + delivery
1000 sq ft × $3.00–$8.00/sq ft
Prices vary by location and time. Contact local suppliers for accurate quotes.
For general step-by-step instructions, read our complete Driveway Thickness and Driveway Cost.
Driveway Volume by Size and Thickness
Driveway concrete is measured in cubic yards. The formula: length (ft) × width (ft) × thickness (inches ÷ 12) ÷ 27. A 20×50 ft driveway at 5 inches: 20 × 50 × (5÷12) ÷ 27 = 15.4 cubic yards before waste.
| Driveway Size | Thickness | Cubic Yards | Bags (incl. 10% waste) |
|---|---|---|---|
| 10×20 ft | 4 in | 2.47 cu yd | 111 bags |
| 10×20 ft | 5 in | 3.09 cu yd | 139 bags |
| 20×20 ft | 5 in | 6.17 cu yd | 278 bags |
| 20×50 ft | 5 in | 15.43 cu yd | 695 bags |
| 24×60 ft | 6 in | 26.67 cu yd | 1,200 bags |
For any driveway over 2 cubic yards, ready-mix delivery is more practical than bagged concrete. A standard two-car driveway at 15+ cubic yards equals one full ready-mix truck — bagged concrete is simply not feasible at that volume.
Recommended Thickness by Use
Driveway thickness is the most important structural decision. Adding one inch costs roughly $0.75–$1.25 more per square foot in material but substantially increases load capacity.
| Use Case | Recommended Thickness |
|---|---|
| Foot traffic only | 3–4 in |
| Passenger cars and SUVs | 5 in |
| Pickup trucks with occasional loads | 5–6 in |
| Heavy trucks, RVs, delivery vehicles | 6 in |
| Constant heavy loads | 6–8 in |
The Portland Cement Association (PCA) recommends 5 inches as the minimum for residential driveways. A 4-inch driveway is often insufficient for vehicle loads and will crack prematurely under normal use.
Reinforcement
Wire mesh (6×6 W1.4/W1.4 welded wire fabric) is the standard minimum for residential driveways. Place it on 1.5-inch chairs at mid-depth — reinforcement resting on the subgrade provides no structural benefit. Rebar (#4 bars on 18-inch centers both ways) is the upgrade choice for heavy loads or poor soil conditions.
Curing and Traffic
New concrete needs time before vehicle loads. Wait 7 days minimum before parking passenger vehicles, and the full 28 days before heavy vehicles. Concrete reaches about 70% of its design strength at 7 days and 99% at 28 days. Avoid deicing salts during the first winter — they cause surface scaling.
For full driveway pour guidance, see How to Pour Concrete. For installed cost estimates, use our Concrete Driveway Cost Calculator.