The invention relates to an electrochemical method for determining the DOC and/or TOC and/or IC content in a water sample by means of anodic oxidation on electrodes in a closed electrolysis cell, wherein the carbon is oxidized at least partially to carbon dioxide (CO2).The carbon dioxide thereby formed is collected in a closed gas space, wherein, in the range of the essentially linear increase in the CO2 content in the gas space, the rate at which this increase takes place is determined and used in an analyzer unit to determine the DOC and/or TOC and/or IC content.