This invention describes an occupant size and weight detection device consisting of a combination of force/load sensors (1), a head position sensor (2, 3), a multidirectional acceleration sensor (5), and a seat position sensor (4) used to determine the weight of an occupant based on weight distribution, body angle and foot position. The goal of the invention is to determine the weight of an occupant who is sitting in the front seat of a vehicle that is subjected to the dynamic forces resulting from the vehicle moving. This technology can be used in applications such as automotive occupant weight and position sensing for use with safety devices such as airbags.