Concrete Calculator
Estimate concrete volume and 40 kg bags from l×w×thickness (m).
How it works
Volume = l×w×thickness; Bags ≈ volume × 60 (1 m³ ≈ 2400 kg)
Assumes ~2400 kg/m³ and 40 kg bags; allow 5%–10% extra.
Worked example
Slab 5 m × 4 m at 10 cm (0.1 m): volume = 5 × 4 × 0.1 = 2 m³.
At 2,400 kg/m³ that is about 4.8 tonnes; order 5%–10% extra for waste.
Notes and limitations
This is geometric volume only — it ignores rebar displacement, uneven subgrade and compaction. Mix design must follow the specified strength and a professional specification; never guess a mix for load-bearing work.