An in-toilet apparatus for discrimination of urine and feces is disclosed. An optical sensor is provided for the analysis of urination and defecation events within a toilet bowl. Additionally, strain gauges are provided to make possible the quantification of urine and feces that a user releases. The combination of data from the optical sensors and strain gauges makes it possible for a user to readily know the mass of their bodily excrements, characterized by excrement type. In several embodiments the optical sensor is a thermal camera mounted on the toilet seat or in the toilet bowl. In other embodiments the optical sensor is a water level sensor. In varying embodiments, strain gauges are located in the toilet seat or in an attached footscale or both.