Semixylenol orange is widely used as a metallochromic indicator in complexometric titrations, particularly for the determination of metal ions such as calcium, magnesium, and zinc. It forms distinct color changes when it binds to these metal ions, making it valuable for endpoint detection in analytical chemistry. Additionally, it is employed in biochemical research to study metal ion interactions in biological systems, aiding in the understanding of metal-related processes in cells and tissues. Its sensitivity to metal ions also makes it useful in environmental monitoring to detect and quantify heavy metals in water and soil samples.