{"id":"concrete-calculator","name":"Concrete Volume Calculator","shortName":"Concrete Volume","canonicalUrl":"https://calcurhome.com/calculators/concrete-calculator","catalogUrl":"https://calcurhome.com/api/calculators","category":{"id":"concrete-masonry","name":"Concrete & masonry","url":"https://calcurhome.com/calculators/category/concrete-masonry"},"language":"en-US","audience":"US homeowners, DIYers and home-project planners","primaryKeyword":"concrete calculator","secondaryKeywords":["concrete cubic yard calculator","how much concrete","ready mix calculator","rectangular concrete volume calculator"],"description":"Calculate general rectangular concrete volume in cubic yards and approximate bag equivalents from dimensions and a custom placement allowance.","directAnswer":"For any rectangular concrete placement, multiply length by width by thickness in feet, divide cubic feet by 27, and add a placement allowance. This page covers general volume and ready-mix quantity. Use the Concrete Slab Calculator when a uniform slab also needs surface-area or material-cost output.","inputs":[{"key":"length","label":"Pour length","unit":"ft","defaultValue":12,"min":0.1,"step":0.1},{"key":"width","label":"Pour width","unit":"ft","defaultValue":10,"min":0.1,"step":0.1},{"key":"thickness","label":"Thickness","unit":"in","defaultValue":4,"min":0.5,"step":0.25},{"key":"waste","label":"Placement allowance","unit":"%","defaultValue":10,"min":0,"max":30,"step":1}],"formula":{"title":"Concrete volume for a rectangular pour","expression":"Order yards = length × width × (thickness in inches ÷ 12) ÷ 27 × waste factor","explanation":"The dimensions produce placed cubic feet after thickness is converted to feet. Dividing by 27 gives cubic yards, and the selected allowance is added to reduce the chance of a short pour."},"measurementGuide":["Measure inside the forms rather than using the excavation’s outside dimensions.","Check thickness at several points because an uneven subgrade increases real concrete volume.","Calculate thickened edges, grade beams, steps, and footings as separate shapes.","Use finished dimensions from approved plans for structural work instead of estimating by eye."],"buyingTips":["Ask ready-mix suppliers about minimum loads, short-load fees, delivery windows, and washout rules.","Confirm strength, slump, aggregate, air entrainment, and admixtures with the project specification.","Use bags only when mixing capacity and placement time allow a continuous, properly finished pour.","Arrange labor, tools, access, weather protection, and curing materials before the truck arrives."],"workedExample":{"title":"General rectangular concrete placement","scenario":"A rectangular pour is 12 ft long, 10 ft wide, and 4 inches thick with 10% extra.","result":"12 × 10 × (4 ÷ 12) ÷ 27 = 1.48 cu yd exact; order estimate = 1.63 cu yd."},"commonQuestions":[{"question":"How much extra concrete should I order?","answer":"Five to ten percent is a common planning range for simple formed work, but irregular excavation or uncertain subgrade can require more. Measure carefully and ask the supplier or contractor; excess concrete also needs a lawful disposal plan."},{"question":"How many 80-pound bags equal one cubic yard?","answer":"At a typical listed yield of 0.60 cubic foot per 80-pound bag, one cubic yard requires 45 bags because 27 ÷ 0.60 = 45. Product yields vary, so the package label controls your final count."},{"question":"When should I use the Concrete Slab Calculator?","answer":"Use the slab-specific calculator when you need uniform slab surface area, order volume, and a material subtotal from a local per-yard quote. Use this general page for rectangular concrete volume without making the page responsible for slab pricing or design."},{"question":"Can I calculate concrete for multiple sections together?","answer":"Yes. Calculate the exact cubic yards of each distinct slab, footing, step, or thickened edge, then add those exact volumes. Apply the placement allowance once to the combined total to avoid compounding waste percentages."}],"sources":[{"name":"QUIKRETE Concrete Mix Product Data","url":"https://www.quikrete.com/pdfs/data_sheet-concrete%20mix%201101.pdf","note":"Manufacturer product data used to cross-check typical bag yields; verify the yield printed on the bag you buy."},{"name":"International Code Council — 2024 International Residential Code","url":"https://codes.iccsafe.org/content/IRC2024P1","note":"Primary model-code source for residential foundations, reinforcement, masonry, and stair safety requirements."}],"defaultCalculation":{"inputs":{"length":12,"width":10,"thickness":4,"waste":10},"result":{"value":"1.63","unit":"cu yd","label":"Concrete to order","lines":[{"label":"Exact placed volume","value":"1.48 cu yd"},{"label":"Order volume in cubic feet","value":"44 cu ft"},{"label":"Approx. 80-lb bags","value":"74 bags"},{"label":"Pour footprint","value":"120 sq ft"}],"summary":"Plan for 1.63 cubic yards after the selected placement allowance.","note":"Bag count assumes 0.60 cubic foot per 80-pound bag. Confirm package yield and have a professional verify structural thickness, mix, reinforcement, and subgrade."}},"reviewedOn":"2026-07-23","disclaimer":"Planning estimate only. Verify product coverage, supplier rounding, local codes and structural requirements before purchase or construction."}