The classic method of moisture content determination in solids is the loss on drying method. Using the principle of evaporation, a sample material is weighed before and after drying. Percent moisture is computed by dividing the change in weight of the sample by the initial weight multiplied by 100 percent.
Other moisture content determination methods include the Dean and Stark method using distillation, Karl-Fisher titration, calorimetry, spectroscopy, thermogravimetry, and vapor pressure methods. The particular method used in determination depends on the type of sample, its state of matter, the amount of water in the sample, the water content and the volatility of other components in the sample.