In the biopharma and cell culture engineering industries, a key objective is to increase process productivity and product titer. Process optimization is easier with a sensor for online viable cell density. Capacitance technology has become a reliable, inline, real-time Process Analytical Technology (PAT) tool for measuring viable cell density in bioprocesses. Various groups have reported productivity enhancements using capacitance to determine process control events, with a few examples highlighted in this application note. For example, optimizing feeding strategies in mammalian or microbial process by calculating feeds from online cell density offered productivity increases from 15-62%. Such improvements offer numerous advantages, including reduced costs, heightened efficiency, expanded capacity, and expedited time to market.