Provided is an input device including a coordinate input unit having plural capacitance detection units, a capacitance measurement unit that measures capacitance for each of the plural capacitance detection units, and performs an AD conversion on the measured capacitance to output the converted capacitance as a measurement signal, and a control unit that controls the capacitance measurement unit, calculates a data signal by arithmetically operating the measurement signal, stores the data signal in association with coordinate information of the capacitance detection unit, and outputs a control signal. The control unit calculates a difference value between a predetermined reference value and the data signal at a constant time interval, performs a weighted average process on the data signal and the predetermined reference value to update and store a value on which the process is performed as a new reference value, and changes a weight given to the weighted average process.