Used as a pH indicator in analytical chemistry, particularly in titrations and pH testing where a sharp color change is required. It changes color in the pH range of approximately 8.2 to 9.8, transitioning from colorless to pink or red, making it suitable for detecting weakly basic solutions. Commonly employed in water quality testing, educational laboratory experiments, and in formulations where a precise alkaline endpoint needs to be identified. Its sensitivity in the alkaline range makes it useful for monitoring pH in buffers and biological preparations.