One of the most tedious, time consuming and demanding tasks confronting the deck officer is calculation of the correct distribution of the vessel's cargo and ballast. Calculations, using the loading manuals supplied by the shipbuilder, are cumbersome and mistakes can easily be made. As discussed in this article, the appearance of loading calculators and their improvement over the years have greatly eased the calculation of bending moments and shear forces and the distribution of cargo to suit the permissible stresses. At the same time, improvements in micro-computers have made their price more accessible. Specific products available from manufacturers are described.