One bag cement (50kg) = 1.25cubic feet= 0.035m3

If I am mixing cement to make a support base,the is 1ft by 1ft,how much cement do I need?

0.03539 cum

1 cubic foot

0.03472 cum

One bag of cement containing 42.5 kg is 1 cubic feet.

It depends on several factors, but in general according to special formulas 1 bag cement volume in cubic meter:- volume of 1 bag cement (50 kg) is around 0.034722 m3 (cubic meter). So answer is quite simple. More info about types of cement you can find on https://www.mgnbm.co.uk/building-products/cements-aggregates/cements/ and also check prices.

0.182 cubic meter in 1 bag cement

0.028316847 cubic meters (= 1 cubic foot)