Electrochemical CO2 reduction (eCO(2)R) is a promising strategy to transform detrimental CO2 emissions into sustainable fuels and chemicals. Key requirements for advancing this field are the development of analytical systems and of methods that are able to accurately and reproducibly assess the performance of catalysts, electrodes and electrolysers. Here we present a comprehensive analytical system for eCO(2)R based on commercial hardware, which captures data for >20 gas and liquid products with <5min time resolution by chromatography, tracks gas flow rates, monitors electrolyser temperatures and flow pressures, and records electrolyser resistances and electrode surface areas. To complement the hardware, we develop an open-source software that automatically parses, aligns in time and post-processes the heterogeneous data, yielding quantities such as Faradaic efficiencies and corrected voltages. We showcase the system's capabilities by performing measurements and data analysis on eight parallel electrolyser cells simultaneously.