Acid Chrome Blue K is widely used as a metallochromic indicator in complexometric titrations, particularly for the determination of metal ions such as calcium, magnesium, and aluminum. It forms distinct color changes in the presence of these ions, making it valuable in analytical chemistry for endpoint detection. Additionally, it is employed in histology and biological staining to differentiate tissues and cellular structures under microscopic examination. In industrial applications, it serves as a dye for coloring textiles, leather, and paper, providing vibrant and stable hues. Its chelating properties also make it useful in water treatment processes for metal ion sequestration.