On-line analysis of of-gas composition (CO2 andO2) is crucial for understanding and optimizing bioprocesses. Culture Biosciences has integrated of-gas analyzers into every bioreactor in their high-throughput cultivation system, allowing continuous tracking of important metabolic information such as OUR and CER. Here, the performance and stability of Culture Bioscience’s custom-made analyzers is assessed and compared with a comparable commercially available of-gas analyzer.