Transformation diagrams are one of the most reliable ways to predict the thermal behavior of the materials. In this work, the crystallization process of several metallic glasses and polymer materials was analyzed and two isoconversional methods are applied to perform kinetic analysis of non-isothermal heating/cooling and isothermal processes. Moreover, the diagrams were constructed from modeling experimental data without the knowledge of the kinetic model. There was a good agreement between experimental data and the calculated curves, which verifies the reliability of the method and the validity of the rate constant model description.