Diphenylcarbazone is widely used as an indicator in analytical chemistry, particularly for the detection and quantification of metal ions. It is highly effective in complexometric titrations, where it helps identify the endpoint by forming colored complexes with metals such as mercury, lead, and cadmium. This property makes it valuable in environmental testing, where it is employed to monitor and measure heavy metal contamination in water and soil samples. Additionally, it is utilized in laboratory research for studying metal-ligand interactions and in quality control processes for industries that handle metal-based products. Its sensitivity and specificity for certain metals make it a crucial reagent in various chemical analyses.