This application note describes three different measurement methods of the ohmic drop and the ohmic resistance presented. Current interrupt and positive feedback are fast methods, but care is necessary for their use in order to avoid data misinterpretation or damage to the setup. EIS, on the other hand, is a more reliable method to determine the ohmic resistance. The ohmic drop can be compensated by the potentiostat during the measurement, or a mathematical correction can be applied to the data.