A bite force measuring system comprising a mouthpiece interfaced to a control unit. The mouthpiece comprises memory for storing calibration parameters. The mouthpiece comprises a fluid-filled compressible cavity, and a fluid-pressure-sensing device for measuring a pressure of a fluid contained in the fluid-filled compressible cavity. The mouthpiece comprises a communication interface for transmitting the calibration parameters and the measured pressure to the control unit. The control unit comprises a communication interface for receiving the calibration parameters and the measured pressure from the mouthpiece. The control unit comprises a processing unit for calculating a bite force corresponding to the measured pressure. The calibration parameters and the measured pressure are used calculating the bite force corresponding to the measured pressure. The calibration parameters may consist of coefficients of a polynomial equation for calculating the bite force by applying the polynomial equation to the measured pressure. A calibration method is also disclosed.