Free · 6 calculators

Concrete volume calculators

Pick the shape you are pouring. Every calculator returns the volume in cubic yards, cubic metres and cubic feet, then the number of bags in each common size - with an optional waste allowance. Work in feet, inches, metres or centimetres. If you want the arithmetic behind the answer, how many bags of concrete do I need walks it end to end, including where the bag yields come from.

SlabConcrete slabPatios, floors, driveways and pads - length × width × thickness.FootingConcrete footingStrip and spread footings - length × width × depth.ColumnColumn & sonotubeRound columns and sonotube piers - π·r²·height.Post holesPost holeFence and deck post footings - hole volume, less the post.StepsConcrete stepsSolid poured stairs - stacked step cross-sections × width.CurbCurb & gutterCurbs and curb-and-gutter - cross-section × run.

Estimates for planning. Quantities are computed from standard volume formulas and typical bag yields, and are intended for ordering material. Structural and load-bearing work must follow your local building code and a qualified engineer's specification.