Pressure and touch sensitivity is crucial for intuitive human-machine interfaces. Here, we investigate the use of different microstructured elastomers for use as dielectric material in capacitive pressure sensors. We use fi nite element modeling to simulate how different microstructures can reduce the effective mechanical modulus. We found that pyramidal structures are optimal shapes that reduce the effective mechanical modulus of the elastomer by an order of magnitude. We also investigate the dependence of spacing of the pyramidal microstructures and how it impacts mechanical sensitivity. We further demonstrate the use of these elastomeric microstructures as the dielectric material on a variety of fl exible and stretchable substrates to capture touch information in order to enable large area human-computer interfaces for next generation input devices, as well as continuous healthmonitoring sensors. Stanford 94305 , USA E. Eason Mechanical Engineering Department Stanford 94305 , USA