Abstract: The present invention provides a formability analysis method for sheet metal forming processes with the universal formability technology (UFT) by using finite element analysis (FEA) and circle grid analysis (CGA). This method comprises the processes of processing mechanics data of strains and displacements from a defective formed workpiece obtained from FEA and CGA, creating formability diagrams, calculating formability indexes, identifying formability status through comparing the formability indexes with the formability diagrams, and developing two formability solutions metal forming defects. One is the reliability ranges of the stamping process, which is described with the stamping process window including the formability, material and tooling windows; the other is the solution for stamping defects presented as the amounts of metal flow adjustments and the intervals of the associated stamping variables.