This application is related to a system for measuring eye pressure and related methods. In some embodiments, the system includes a pressure sensor and a processor. The pressure sensor takes a measurement from a contact with an eyelid. The processor includes an engine that is built from a set of items, each comprising a list of user attribute values, the eye pressure measured by the pressure sensor, and the actual eye pressure level, and can estimate the actual eye pressure level and normalized eye pressure level. Given a new measurement of a users eye pressure made by the pressure sensor, the processor identifies the user attribute values for the user and runs the engine to estimate the actual eye pressure level and the normalized eye pressure level.