Concrete Calculator
Work out concrete volume for a rectangular slab — footing, floor slab, or pad. Add wastage and optional bag counts for site estimates.
Measurements
Enter yield per bag above to price by bag instead of per m³.
How this is calculated
Volume = length × width × thickness (converted to cubic metres internally), then multiplied by (1 + wastage ÷ 100).
Bags = volume ÷ yield per bag, rounded up (when bag yield is provided).
Ready-mix is often ordered in m³; on-site mixes may be counted in bags — use the yield figure from your mix design or supplier.
Related reading
Estimates only — slab thickness, mix design, and site conditions affect true volume. Confirm with your supplier or batching plant.