Concrete slab calculator
PROCubic yards and bags for a concrete slab.
Inputs
Result
Cubic yards
1.23
80 lb bags
56
60 lb bags
75
The formula
cu yd = (L × W × thick/12) ÷ 27. 80 lb bag ≈ 0.6 cu ft.
Worked example
10 × 10 × 4" = 33 cu ft ≈ 1.24 yd³ or 56 bags of 80 lb.
Frequently asked
›Bag or ready-mix?
Under 1 cu yd: bags. Over 1 cu yd: order ready-mix.