How much concrete do I need for a 12×12 shed slab?
≈ 1.78 cubic yards
That’s about 80 bags of 80-lb concrete mix (or 107 60-lb bags) for a 12×12 area at 4″ thick.
A 12 ft × 12 ft shed slab is 144 square feet. Poured at the standard 4-inch slab thickness, that’s 48.0 cubic feet of concrete — about 1.78 cubic yards.
| Area | 144 sq ft |
| Thickness | 4 in |
| Volume | 1.78 cu yd (48.0 cu ft) |
| 80-lb bags | 80 bags |
| 60-lb bags | 107 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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