How many bags of cement do I need for a concrete slab?

Enter the slab length, width, thickness and mix ratio and Fundi Calculator works out the cement bags, sand and ballast — for a 1:2:4 mix it applies the standard 1.54 dry factor and shows the full working.

How do I calculate building materials for a house in Kenya?

Fundi Calculator estimates concrete, walling stones or blocks, plaster, paint, roofing sheets and tiles from your measurements, with the assumptions shown so nobody inflates the quantities.

How many machine-cut stones are in a square metre?

About 11.6 standard 400×200 mm stones per square metre of wall including a 10 mm joint; the calculator adds a wastage allowance.

Fundi Calculator — cement, sand, ballast, stones, paint, roofing & tiles

Estimates for budgeting — agree final quantities with your fundi or quantity surveyor; site conditions vary.

Concrete — slab, strip footing or column

Element preset

Length (m)

Width (m)

Thickness (m)

Mix ratio

Material densities, coverages and lap allowances vary by supplier and site. Nothing is uploaded — everything runs in your browser.