Concrete Calculator Please use this calculator to estimate the quantity of ready mixed concrete you require for your project. Concrete Calculator For a slab, enter the length and width of the slab and the average depth, and for a trench, enter the total length of the centreline of the trench, and the average width and depth. m cm in ft yd m cm in ft yd cm m in ft yd Calculate reset Give us a call on 0114 256 1660 to speak to a member of our team who will be happy to help.