Estimate concrete volume in cubic yards and 80lb bags for slabs, footings and columns from dimensions. Dimensions stay on your device with offline math.
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50 cu ft • 84 × 80 lb bags (0.6 cu ft each)
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About forty-five eighty-pound sacks fill one cubic yard of poured concrete. Ten feet by ten feet by four inches needs 1.24 yards or fifty-six sacks in one read. Results round upward with waste in one pass. Each yard sum runs on-device net-off privately without uploads.
Yard sums stay in-tab alone without sending or sign-in linkage for confidential job costing. Three slabs with nine dimensions compute on-device offline instantly with no retention. Sizes hold local, need no network, and erase on close automatically. No account is requested for estimation at any time.
Order five to ten percent extra for spillage, uneven subgrade, and form absorption. Ten by ten by four-inch slab at 1.24 yards or fifty-six sacks becomes sixty-two sacks with ten percent buffer. Over-excavated edges consume surplus quickly. Confirming supplier minimums avoids second delivery fees.
Footings multiply linear length by width by depth for trench volumes, while slabs multiply area by thickness. Twenty-foot trench twelve inches wide twelve inches deep needs 0.74 yards versus 1.24 for patio slab. Cylindrical columns use pi times radius squared times height. Selecting shape before dimensions prevents unit errors.
Eighty-pound sacks suit large pours with fewer bags and lower per-yard cost, while sixty-pound sacks ease lifting for solo workers. One cubic yard needs forty-five eighty-pound versus sixty sixty-pound sacks. Comparing 1.24-yard patio at fifty-six eighties versus seventy-five sixties guides back strain versus trips tradeoff.
Yardage converts slab dimensions into orderable pour volumes and sack purchases with waste buffering. Ten feet by ten feet by four inches shows 1.24 yards and fifty-six eighty-pound sacks in one read. Crews pouring five yards daily and retailers stocking forty-five sacks per yard depend on accuracy. Reference table benchmarks pours comprehensively | Dimensions | Cubic feet | Yards | Eighty-pound sacks | 10 by 10 by 4 inches | 33.3 | 1.24 | 56 | 12 by 12 by 4 inches | 48.0 | 1.78 | 80 | 20-foot footing 12 by 12 inches | 20.0 | 0.74 | 34. Edge case of irregular subgrade eats extra volume unexpectedly. Limitation excludes rebar displacement and form expansion. Try three sizes to build ordering confidence and see /unit-converter for length conversions.
Length times width times depth gives cubic feet over three dimensions, feet divided by twenty-seven give yards in one split. Ten by ten by 0.33 feet gives 33.3 feet or 1.24 yards, sacks divide yards by forty-five per eighty-pound unit. Second example at twelve by twelve by 0.33 gives 48 feet or 1.78 yards for eighty sacks. Conversion table shows math stepwise | Step | Formula pattern | Substitution example | Volume feet | 10 times 10 times 0.33 | 33.3 cubic feet | Yards | 33.3 divided by 27 | 1.24 yards | Sacks | 1.24 times 45 | 56 sacks. Edge case of rough excavation demands five to ten percent surplus for safety. Limitation ignores slump and aggregate ratios. Add waste before calling supplier to avoid short loads.
Pick slab, type ten feet by ten feet by four inches to see 1.24 yards and fifty-six sacks with intermediate cubic feet displayed. Add ten percent waste to buy sixty-two sacks in two clicks, covering spillage and absorption. Test twelve-foot span for 1.78 yards and eighty sacks to scale intuition across sizes. Verify footing trench at twenty feet for 0.74 yards as alternate shape. Edge case of cold joints requires continuous pour planning beyond volume calculations. Limitation covers pour sums only, excluding rebar, mix design, or soil proof for twenty yards. Order spare mix and verify thickness with screed. Check ten by ten by four inches for 1.24 yards then ten percent waste for sixty-two to lock ordering confidently.