An electrometer using complementary metal–oxide–semiconductor bilateral switches for automatic range control is described. Based on a dual-switching configuration, the electrometer is capable of current measurement over eight orders of magnitude. Together with a voltage shifter, this circuit provides a quasilinear analog output for the measurement of input dc current between10−3and10−12 A.The application of integrated circuits makes the whole system compact and extremely low cost. ©1997 American Institute of Physics.