Inflatable pads are used in multiple applications, e.g. as mattresses or protective equipment. In this work, we propose to treat these inflatables, made of two planar membranes sealed according to periodic patterns, typically parallel lines or dots, as metamaterials. By considering novel sealing patterns with 6-fold symmetry, we are able to generate a family of inflatable materials whose macroscale contraction is isotropic and can be modulated by controlling the parameters of the seals. We leverage this property of our inflatable materials family to propose a simple and effective algorithm based on conformal mapping that allows us to design the layout of inflatable structures that can be fabricated flat and whose inflated shapes approximate those of given target freeform surfaces.