The free and confined inflation of isotropic homogeneous membranes of general shape are considered. The material is assumed to obey the Mooney-Rivlin constitutive model, and the resulting partial differential equations, governing the deformation field, are solved using a Galerkin based finite-element procedure. The method is illustrated through examples of both free and confined inflation, as well as simultaneous stretch and inflation. Measurements were carried out on the final thickness distribution of containers blow-molded in our laboratory. These containers typically cover a wide range of geometry and size, including bottles with handles. Comparison between theory and experiment leads generally to good agreement, despite the limitation of the membrane hypothesis.