Use the yield from the package
Enter the product's yield in cubic feet per bag. The starting yield is a clearly marked example only; change it to match the manufacturer information for the exact product. The required count is rounded up to a whole bag after applying the selected waste percentage.
Bagged mixes may have different yields, coverage, mixing instructions, and intended applications. Follow the package instructions and check whether the volume is sufficient for your project before purchasing.
Example bag calculation
A hypothetical 10 ft × 10 ft × 4 in slab is about 33.33 cu ft before waste. With 10% extra and a user-entered example yield of 0.6 cu ft per bag, the arithmetic rounds up to 62 bags. This count changes with the actual product yield.