How much concrete do it take to pour a 9' x9'x4' slab?

To calculate the amount of concrete needed for a 9' x 9' x 4' slab, first determine the volume in cubic feet by multiplying the dimensions: 9 x 9 x 4 = 324 cubic feet. Since concrete is typically sold by the cubic yard, convert cubic feet to cubic yards by dividing by 27 (there are 27 cubic feet in a cubic yard). Therefore, you would need approximately 12 cubic yards of concrete for the slab.