Concrete Bag Calculator
Professional-grade bag estimation for slabs, footings, and post holes — with live 3D preview, rebar estimates, and local store finder.
1 · Project Type
2 · Dimensions
Standard driveway: 4 in · Patio: 3–4 in · Structural: 6 in
3 · Live Preview
4 · Material Estimate
All Bag Sizes
Rebar Estimate (18″ grid)
5 · Get Materials
Nearby Hardware Stores
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💡 Pro Tip: Consider Ready-Mix
At 1.36 yd³, a ready-mix truck may save time and labour. Typical delivery: $150–$200/yd³ with ~$1,000 minimum.
Standard driveway: 4 in · Patio: 3–4 in · Structural: 6 in
Concrete Calculator — Expert FAQs
Common questions from contractors and DIYers about concrete bag estimation.
How This Calculator Works
This tool calculates the volume of your concrete pour in cubic feet using exact geometric formulas, then converts to cubic yards and divides by each bag's published yield to give you precise bag counts. A configurable waste factor (5–15%) is applied to account for spillage, overpour, and form imperfections. All calculations follow industry standards used by licensed concrete contractors across Canada and the USA.
Yields are approximate — verify bag counts with your local supplier before purchasing.