p-Dimethylaminobenzalrhodanine is primarily used as a reagent in analytical chemistry for the detection of heavy metals, particularly silver, mercury, and lead. It forms colored complexes with these metals, enabling qualitative and quantitative analysis, often via spectrophotometry. In organic synthesis, it serves as an intermediate for the preparation of dyes and other complex organic compounds. Its sensitivity to metal ions also makes it valuable in environmental monitoring for assessing metal contamination in water and soil samples.