Total freezing time calculations have been carried out by considering two partial times; the precooling, corresponding to the time from the initial temperature to the initial solidification temperature, and the tempering, from the initial solidification temperature to the final temperature. The samples having a slab geometry were the Karlsruhe Test Substance (methyl cellulose gel) and different kinds of meats. The calculation method used the closed form solution for the precooling period and Plank＇s equation with the equivalent volumetric enthalpy variation for the tempering time. Some hypotheses were adopted to simplify the temperature distribution in the sample at the end of the two periods and to use the same thermophysical properties for each group of samples. The accuracy obtained makes this method valuable enough for many practical uses in freezing time calculations of foods.