A method and device for reading an electronic code. An alternating electrical signal is brought to the code being measured with the aid of electrodes, and the current or voltage travelling through the electrodes is measured. The real and the imaginary components of the current or correspondingly the voltage are defined. The electrodes, being on an essentially lossless surface, an angle correction is made to the real and imaginary components of the current or the voltage in such a way that substantial changes in the current take place only in the imaginary component of the current or voltage.