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Concrete Calculator

Volume, ready-mix order size and bagged-material quantities for slabs, footings and post holes.

Volume required (incl. 10% waste)

1.32 m³

Ready-mix order: 1.35 m³ · Approx. weight 3.2 t

Mixing it yourself? (C20 guide)

Cement, 25kg bags16
All-in ballast2.5 t
Ballast bulk bags (~850kg)3

Guide only. Confirm mix strength (C20/C25/C35) with your structural engineer. Need foundation drawings? Request a free quote.