The ELVA project (Advanced Electric Vehicle Architectures) was aimed at developing specific vehicle concepts and architectures for electric vehicles where no adaptations of existing internal combustion vehicles were made, taking advantage of the new freedoms in design that electric powertrains provide. The project, characterized by an intensive interaction among the partners, was co-funded under the European Commission's 7th Framework Programme and included in the consortium ika (coordinator), Volkswagen, Renault, CRF, Continental, SAFER and Applus+ IDIADA.The paper deals with the development of a web design support tool devoted to designers for the definition of the powertrain components that fulfil the main vehicle targets (range, acceleration and maximum speed) complying with the current regulations and market practices. The main advantage of the tool is that it focuses on the design putting together calculations that typically belong to different fields.The development consisted of two phases. Firstly, the creation of an internal model which interactively represents the vehicle development problem as a set of requirements in terms of weight and battery size needed to fulfil the targets. Afterwards, it was adapted to run in a web server for the variety of inputs combinations within its strict calculating limitations. The web tool has a simple interface to introduce the targets and vehicle characteristics such as battery technology, drag or tire class. It provides values for components sizing, powertrain architecture recommendations and, in some cases, suggestions for inputs optimization. When the inputs do not provide a feasible solution, warning and improvement suggestions appear.