Volume & Material

The deterministic volume & material cluster — the highest-demand concrete queries: a concrete calculator (area × thickness → cubic yards + bags), a concrete slab calculator (rectangular or L-shape), a bags-of-concrete calculator across 40/60/80 lb, a ready-mix vs bags compare with the breakeven, a concrete cost-per-yard estimator, a rebar calculator (linear ft from your grid spacing), a gravel / sub-base calculator (yd³ + tons), a sonotube / column / footing volume calculator, and a concrete block / wall count calculator. A footing, slab or rebar figure here is a concrete VOLUME or QUANTITY, never a structural design.

Confirm yield against your product’s bag/spec sheet and order a little extra (5–10%) for spillage, uneven subgrade and over-excavation. Bag yields and coverage vary by mix and brand.
Concrete calculatorFree concrete calculator: turn length, width and thickness into cubic feet, cubic yards and 40/60/80 lb bags, with a waste allowance and the formula shown.Concrete slab calculatorConcrete slab calculator for rectangular and L-shaped slabs: add two rectangles, pick a thickness and get cubic yards and bags with the formula shown.Bags of concrete calculatorBags of concrete calculator: enter length, width and thickness to see how many 40, 60 and 80 lb bags you need, side by side, with the yields shown.Ready-mix vs bagsReady-mix vs bags calculator: compare ready-mix delivery against bagged concrete for your pour using your own prices, and see the cheaper option and difference.Concrete cost per yardConcrete cost per yard calculator: total a ready-mix order from your own price per cubic yard plus delivery, short-load and pump fees. Planning estimate.Rebar calculatorRebar calculator: get the linear feet and bar count for a slab grid from your on-center spacing, with a lap allowance. A quantity, not a structural design.Gravel / sub-base calculatorGravel sub-base calculator: get cubic yards and tons for the compacted base under a slab or driveway, with a compaction allowance and the density shown.Sonotube / footing calculatorSonotube and footing calculator: total the concrete for round column tube forms plus a rectangular footing pad in cubic feet, cubic yards and bags.Block / wall count calculatorConcrete block calculator: count standard 8x16 blocks and mortar bags for a wall from length and height, with a waste allowance. Count, not a design.

Every Volume & Material tool is calculated server-side — visible immediately — with its formula, a worked example and a reference table, and works on the quantities you measure and the prices you enter from your own quotes. Background reading is in the guides.