Formability tests simulating stretch-bend conditions have been developed for simple angular and hemispherical contours. The tests were designed to determine the influence of material and geometrical variables on sheet metal formability. Data obtained from the tests have produced families of curves relating the punch radius (R) and sheet thickness (t) to the height of the configuration at failure (H). The (RtH) curves define formability envelopes which contain all possible combinations of (R), (t) and (H). Results obtained for AK steel, HSLA-F50, dual phase 80 and 2036-T4 aluminum show that the (RtH) curves can be used as guidelines for designing and stamping sheet metal parts. They can be especially helpful in determinations concerning the ranking, downgaging, selection and substitution of sheet metal.