Dimethylsulfonazo III is primarily used as a sensitive and selective reagent for the spectrophotometric determination of metal ions, particularly calcium, magnesium, and barium, in various analytical applications. Its ability to form stable complexes with these ions makes it valuable in water quality testing, where it helps assess hardness levels. Additionally, it is employed in biochemical research to study metal ion interactions in biological systems, aiding in understanding cellular processes. The compound’s color change upon binding with specific ions allows for precise and efficient detection in laboratory analyses, including as a colorimetric indicator in titration techniques.