Concrete Bag & Cubic Yard Calculator for Multiple Pours
Estimate slab and round post-hole concrete volumes, bag quantities, overage and material cost with a printable CSV takeoff.
Add a concrete pour
For round holes, “length” is ignored and “width” is the diameter in inches.
Concrete order estimate
Approximate volume only. Product yields vary. Verify bag labels, local requirements, base compaction, reinforcement and delivery options; this is not structural engineering or mix guidance.
Calculate concrete bags and cubic yards for several pours
Contractors and DIY builders may know slab dimensions but struggle to reconcile bag counts, total weight and ready-mix volume. ConcreteYield sums rectangular slabs and round post holes separately, applies an explicit overage, then converts cubic feet to cubic yards and estimated whole bags.
How the math works
Rectangular volume = length × width × thickness in feet. Round-hole volume = π × radius² × depth, multiplied by hole count. Divide the volume including your chosen allowance by the product-specific bag yield and round up. Example yields of 0.60 ft³ for an 80 lb bag and 0.45 ft³ for a 60 lb bag are approximate; the package is authoritative.
Free competing calculators already exist. The possible differentiation is multi-section takeoffs, transparent yields, and CSV export—not a claim of higher structural accuracy.