An exercise machine including a weight measurement system which provides a signal representative of a user's weight. An embodiment of the weight measurement system includes at least one load cell outputting a signal used by a microprocessor to determine an accurate value of the users weight. An embodiment of the weight measurement system includes a plurality of load cells using a Wheatstone bridge configuration to output a signal representative of a user's weight regardless of whether the weight is evenly distributed across each load cell. A calibration process calibrates the load cells for each exercise machine.