Compare common bag sizes using nominal dry-mix yields, then add a waste allowance before buying.
Results use your measurements and editable assumptions. Verify product coverage, density, waste and order rounding with the supplier before purchasing.
Bags = project cubic feet ÷ nominal yield per bag, rounded up.
BuildCalc converts measurements to a consistent internal unit, applies your project geometry and only then adds the selected waste allowance. Packaging quantities are rounded up because partial bags, blocks or boxes usually cannot be ordered.
Bagged concrete is normally practical for small pours where ready-mix delivery is not economical. Enter the finished dimensions and choose the exact bag size you intend to buy. The calculator uses nominal yields for comparison, but the yield printed on the selected product remains the value to trust for the final purchase.
A 4 ft by 4 ft pad at 4 in thick contains about 5.33 cubic feet before waste. With a 10% allowance, the order volume is about 5.87 cubic feet. At a nominal 0.45 cubic feet per 60 lb bag, that rounds up to 14 whole bags.
Concrete mix is sold in whole bags, and a fractional bag cannot be purchased. Rounding up avoids understating the order quantity.
Yes. Mix design, aggregate and water requirements can change yield. Check the package data for the exact product before ordering.
Published and maintained by EasyTool.me. Review the calculation methodology, verify product-specific values with the supplier, and report reproducible corrections. Last materially reviewed August 16, 2026.