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Free construction planning tool
Concrete Slab Volume Calculator
Estimate concrete volume for a rectangular slab using measured length, width and thickness.
How this calculator works
Length (ft) × width (ft) × [thickness (in) ÷ 12] ÷ 27 × (1 + waste % ÷ 100).
Does not include thickened edges, grade beams, footings, piers, over-excavation, subbase or reinforcement. Calculate those separately.
Use field-verified dimensions. This planning estimate does not substitute for a complete takeoff, structural design or local supplier quote.
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