Upon exiting the column, the ions are measured by an electrical conductivity detector. This detector produces a chromatogram which plots conductivity vs. time. Each ion produces a peak on this graph, the height of which is dependent on the relative ion concentration in the injected solution. These measurements can then be used to determine concentrations of analytes in an unknown sample. To combat possible interference caused by the ions in the mobile phase, a suppressor may be used to remove the unwanted electrolyte prior to the conductivity measurement. As the solution passes through the suppressor, ions in the eluent are replaced with a nonionic species. Alternatively, if the eluent is sufficiently dilute or has a low conductivity, the use of a suppressor is not necessary.

Since 1975 ion chromatography has been widely used in many branches of industry such as environment, electricity, sanitation, energy, agriculture, food and beverage, pharmaceutical, chemical, petrochemical and many other fields. The main beneficial advantages are reliability, very good accuracy and precision, high selectivity, high speed, high separation efficiency, and low cost of consumables. Ion chromatographs are able to measure concentrations of major anions, such as fluoride, chloride, nitrate, nitrite, and sulfate, as well as major cations such as lithium, sodium, ammonium, potassium, calcium, and magnesium in the parts-per-billion (ppb) range. Concentrations of organic acids can also be measured through ion chromatography.