Device for tracking a subject's daily urine output comprising - a receptacle having a bottom surface and sidewalls defining an open-ended inner volume for the filling of a fluid, said open end being a top of the receptacle; - a capacitive sensor circuit configured for measuring the height of the fluid filled into the receptacle within a capacitive sensing area; said sensor circuit comprising a sensor plane forming at least one first layer within the sensor circuit, at least two capacitive surface electrodes, a plurality of electrical connectors that couple the capacitive surface sensor electrodes to the sensor plane, and a ground plane forming at least one second layer within the sensor circuit; wherein the capacitive surface electrodes have substantially the same surface area and are arranged along at least one sidewall of the receptacle at substantially different distances from the bottom surface such that the capacitive sensing area extends substantially upwards from the bottom surface; and - an electronic module comprising a processing unit connected to the capacitive sensor circuit which is configured to: - receive fluid height data from the capacitive sensor circuit - determine, from said fluid height data, a corresponding urine volume - optionally assign a timestamp to said urine volume; and - store said, optionally timestamped, urine volume on a memory unit; - characterised in that the device further comprises an electrical shielding sandwiched between the sensor plane and the ground plane; wherein the electrical shielding fully encloses the sensor plane apart from the capacitive surface sensor electrodes such that it shields the capacitive sensing area from interference and minimizes parasitic capacitance between the sensor plane and the ground plane. - a receptacle having a bottom surface and sidewalls defining an open-ended inner volume for the filling of a fluid, said open end being a top of the receptacle; - a capacitive sensor circuit configured for measuring the height of the fluid filled into the receptacle within a capacitive sensing area; said sensor circuit comprising a sensor plane forming at least one first layer within the sensor circuit, at least two capacitive surface electrodes, a plurality of electrical connectors that couple the capacitive surface sensor electrodes to the sensor plane, and a ground plane forming at least one second layer within the sensor circuit; wherein the capacitive surface electrodes have substantially the same surface area and are arranged along at least one sidewall of the receptacle at substantially different distances from the bottom surface such that the capacitive sensing area extends substantially upwards from the bottom surface; and - an electronic module comprising a processing unit connected to the capacitive sensor circuit which is configured to: - receive fluid height data from the capacitive sensor circuit - determine, from said fluid height data, a corresponding urine volume - optionally assign a timestamp to said urine volume; and - store said, optionally timestamped, urine volume on a memory unit; - characterised in that the device further comprises an electrical shielding sandwiched between the sensor plane and the ground plane; wherein the electrical shielding fully encloses the sensor plane apart from the capacitive surface sensor electrodes such that it shields the capacitive sensing area from interference and minimizes parasitic capacitance between the sensor plane and the ground plane. - receive fluid height data from the capacitive sensor circuit - determine, from said fluid height data, a corresponding urine volume - optionally assign a timestamp to said urine volume; and - store said, optionally timestamped, urine volume on a memory unit; - characterised in that the device further comprises an electrical shielding sandwiched between the sensor plane and the ground plane; wherein the electrical shielding fully encloses the sensor plane apart from the capacitive surface sensor electrodes such that it shields the capacitive sensing area from interference and minimizes parasitic capacitance between the sensor plane and the ground plane.