The presence of nonmetallic inclusions significantly affects the downstream processes of any liquid metal and compromises the quality of final products. Currently, inert gas injection is one of the processes for removing inclusions from liquid metals. The main target of inert gas injection is to form small bubbles that attach to the nonwetting surfaces of inclusions, facilitating their floatation to the surface of the molten bath. However, the efficacy of inclusion removal greatly depends on the sizes of gas bubbles generated within the liquid metal. Notably, small bubbles, forming at the orifice of gas injection nozzles, will normally coalesce into larger bubbles. Hence, a precise knowledge of their size and distribution within the liquid metal plays a very important role in maintaining optimum bubble size ranges. This range is ideally around 500 μm diameter, to also remove sub-50 μm diameter inclusions. This study introduces an in situ, real-time method for measuring bubble sizes and their distribution in liquid metals. It is primarily based on the liquid metal cleanliness analyzer (LiMCA) system. The LiMCA system was initially developed by Prof. Roderick Guthrie and Dr. Don Doutre at the McGill Metals Processing Centre (MMPC). LiMCA analyzers now serve as a tool for detecting inclusions in various liquid metals such as aluminum and steels. In the present study, a modified design of the LiMCA system was employed to investigate the sizes of the microbubbles formed. The successful detection and measurement of bubble size emphasizes the viability of LiMCA theory in effectively monitoring microbubbles in various liquid melts.