A processing system for capacitance sensing includes a sensor module and a determination module. The sensor module includes sensor circuitry coupled to sensor electrodes, the sensor module configured to generate sensing signals received with the sensor electrodes. The determination module is connected to the sensor electrodes and configured to obtain, for a predetermined timeframe, a profile from the sensing signals, obtain, for the predetermined timeframe, a noise statistic, and calculate, for the predetermined timeframe, a data signal statistic for the predetermined timeframe using the profile. The determination module is further configured to calculate a signal to noise ratio (SNR) by dividing the data signal statistic by the noise statistic. When the SNR satisfies a predetermined detection threshold, an input object is detected in a sensing region of the capacitance sensing input device.