Prediction criterions for the formabilities of perovskite-type oxides are obtained by using the empirical structure
map methods constructed by two parameters octahedral factor (rB/rO) and tolerance factor, on this structure map, simple
point representing systems of forming and non forming are distributed in distinctively different regions. In this paper
we found that the octahedral factor, is as important as the tolerance factor with regards to the formability of perovskitetype
oxides. We have applied the proposed model to 173 ABO3 perovskites and it can be used to search for new
perovskite-type oxides by screening all possible elemental combinations.