Indole is widely used in the fragrance industry, particularly in perfumery, where it contributes floral, jasmine-like, and slightly animalic notes. It is a key component in creating scents for soaps, cosmetics, and fine fragrances, especially those mimicking the aroma of orange blossoms and jasmine.

In pharmaceuticals, indole derivatives play a crucial role in drug development. Many bioactive compounds and medications contain the indole structure, including anti-inflammatory agents, migraine treatments (like triptans), and antipsychotic drugs. Its presence in the core structure of serotonin and melatonin makes it significant in neuroscience and sleep disorder research.

Indole also serves as a building block in organic synthesis, enabling the production of dyes, agrochemicals, and functional materials. In agriculture, indole-3-acetic acid (IAA), a natural auxin, regulates plant growth and is used in tissue culture and rooting formulations.

Additionally, indole is involved in microbiology as a signaling molecule in bacterial communication, influencing biofilm formation and virulence, which makes it relevant in studying bacterial behavior and developing antimicrobial strategies.