In the present communication glass stability (GS) and glass forming ability (GFA) of Ge25−xSe75Sbx (x = 12, 15, and 18) chalcogenide glasses have been calculated in terms of certain thermal parameters, i.e., reduced glass transition temperature (Trg), Hruby number (H), S‐parameter (S), and ΔT. The glassy samples have been prepared by quenching of melt technique. For structure characterization, XRD technique has been used. For thermal analysis Differential Scanning Calorimetery (DSC) has been used. DSC scans have been recorded at different heating rates, i.e., 5, 10, 15, and 20 K min−1. Stability of glassy samples has also been confirmed in terms of activation energy of glass transition calculated by Kissinger relation. All these parameters indicate that GS and GFA both decrease with increase of Sb content in Ge25−xSe75Sbx (x = 12, 15, and 18) glassy series.