Chromotropic acid is widely used as a reagent in analytical chemistry for the detection and determination of formaldehyde. It forms a colored complex with formaldehyde, which can be measured spectrophotometrically, making it valuable in environmental monitoring and industrial hygiene to assess formaldehyde levels in air and water. Additionally, it serves as a dye intermediate in the production of azo dyes, contributing to the vibrant colors in textiles and inks. In biochemistry, chromotropic acid is employed in histochemical staining techniques to identify specific tissue components. It also finds application in the synthesis of pharmaceuticals and organic compounds, acting as a building block in various chemical reactions.