Used primarily as a polymerization inhibitor in the production and storage of reactive monomers such as acrylates, methacrylates, and styrene. It prevents premature polymerization during processing and transportation by scavenging free radicals. Commonly added in small amounts to adhesives, coatings, and resins to extend shelf life.

Also used in the production of paints, printing inks, and lubricants to prevent oxidative degradation and maintain quality.

In cosmetic formulations, it serves as an antioxidant to protect ingredients from oxidation and as a depigmenting agent (known as mequinol) to inhibit melanin production, helping reduce hyperpigmentation, dark spots, freckles, and promote brighter skin.

In analytical chemistry, it serves as a reference compound in antioxidant activity tests. Its ability to stabilize compounds makes it valuable in industrial processes where thermal or oxidative degradation is a concern.