A systematic investigation of glass forming tendency and crystallization kinetics of the Agx-Sb2(1–x)-Te3(1–x) (x=0.16, 0.18, and 0.20) is reported. The alloy of the Ag-Sb-Te glass system, obtained by the rapid quenching technique, is characterized by calorimetric measurements and different thermal analysis for different heating rates. Variation in two important parameters, namely, glass transition temperature Tg and glass forming tendency Kgl, are studied with the variation of Ag content. By analyzing the results that occur with the increase in Ag content, we see that the glass-forming tendency Kgl also increases. However, with the increase in heating rates, the glass transition helps us to find the suitability of an alloy to be used in phase change optical memories/switches. The results are analyzed using Kissinger's equation for the nonisothermal crystallization of materials.