A device for determining the mass flow via a tank venting valve for an internal combustion engine including an intake manifold and a throttle valve, the intake manifold being connected to the tank venting valve and an exhaust gas recirculation system, one measuring transducer each being assigned to the throttle valve and the tank venting valve, and a sensor for the mass flow via the exhaust gas recirculation system being assigned to the exhaust gas recirculation system. In order to be able to determine the mass flow via the tank venting valve with improved accuracy it is provided in such a device that a mass flow normalizer is assigned to the measuring transducers and to the sensor for the mass flow via the exhaust gas recirculation system; the mass flow normalizer picks up, sums, and normalizes the signals of the measuring transducers and the sensor assigned to the mass flows via the throttle valve, via the tank venting valve, and via the exhaust gas recirculation system; a convertor is assigned to the mass flow normalizer; the convertor calculates a virtual throttle valve angle from which an allocator determines the mass flow via the tank venting valve.