3-Hydroxyphthalic acid finds application in the synthesis of various organic compounds, particularly in the production of dyes and pigments. It serves as a key intermediate in the manufacture of colorants used in textiles, inks, and coatings. Additionally, it is utilized in the development of pharmaceuticals, where it acts as a building block for active pharmaceutical ingredients (APIs). In polymer chemistry, it contributes to the creation of specialty resins and polymers with enhanced properties. Its role in analytical chemistry includes its use as a reagent for detecting and quantifying specific substances in complex mixtures. Furthermore, it is employed in research and development for exploring new chemical reactions and pathways, aiding in the advancement of material science and chemical engineering.