KCalc.100 Sq Ft Concrete: How Much Cement?
Quick estimate for cement bags needed for a 100 sq ft slab based on thickness and mix ratio.
Cement needs depend on slab thickness, mix ratio, and bag size. Use the steps below to estimate quickly.
Quick estimate (4 in slab, 1:2:4 mix): About 6 bags (50 kg) of cement for 100 sq ft.
Step-by-step estimate
Example
Area = 100 sq ft Thickness = 4 in = 0.333 ft Volume = 100 x 0.333 = 33.3 ft3 = 0.94 m3 Dry volume = 0.94 x 1.54 = 1.45 m3 Cement (1:2:4 mix) = 1/7 x 1.45 = 0.21 m3 Bags (50 kg) = 0.21 / 0.035 = 6.0 bags
If your slab thickness or mix ratio is different, update the inputs and recalc the volume first.