Used primarily as a pH indicator in analytical chemistry, especially in titration experiments where a visible color change is needed around pH 8.2 to 10.0. It serves as a dye intermediate in the synthesis of certain dyes and pigments due to its aromatic structure and reactivity. Also employed in some industrial processes for monitoring alkalinity in solutions. Its insolubility in water limits use to alcohol-based or mixed solvent systems. Not suitable for use in biological or medical applications due to potential toxicity.