This paper reports and fully characterizes a coulometric nanotitrator and its application for four different types of titrations: precipitation, complex-formation, redox and acid-base nanotitrations. This simple device, composed of Pt or Ag planar electrodes located in a microchannel, gives very reproducible results and yields a linear relationship between the analyte concentration and the equivalence time for concentrations up to 10-2 M of analyte.