How much concrete do I need for a 20×20 driveway?
≈ 4.94 cubic yards
That’s about 223 bags of 80-lb concrete mix (or 297 60-lb bags) for a 20×20 area at 4″ thick.
A 20 ft × 20 ft driveway is 400 square feet. Poured at the standard 4-inch slab thickness, that’s 133.3 cubic feet of concrete — about 4.94 cubic yards.
| Area | 400 sq ft |
| Thickness | 4 in |
| Volume | 4.94 cu yd (133.3 cu ft) |
| 80-lb bags | 223 bags |
| 60-lb bags | 297 bags |
Tip: buy ~10% extra for spillage and uneven subgrade. For a thicker pour (driveways are often 5–6″), use the calculator to adjust.
Change the size → open the concrete calculatorGrab the supplies
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