A mold for forming medical balloons and the balloons formed therefrom are disclosed. The mold has a generally cylindrical inner molding surface for forming a working length of the balloon, and generally cylindrical outer molding surfaces at either end of the mold for forming shafts of the balloon. Joining these outer and inner molding surfaces are taper molding regions composed of two generally conical molding surfaces oriented at two different angles from a longitudinal axis of the mold. A balloon resulting from a manufacturing process using a mold according to the present invention reflects the geometry of the mold and has a unique concave taper profile and a well-defined working length.