Essilor International S.A. is a French company that produces ophthalmic lenses along with ophthalmic optical equipment. It is based in Charenton-le-Pont (near Paris), France, and quoted on the Euronext Paris Stock Exchange. It is a component of the Euro Stoxx 50 share index.

Essilor is responsible for creating Varilux, the world's first progressive lens which corrects presbyopia and allows clear vision in the wearer's near, intermediate and far vision.The company formed from the merger of ophthalmic firms Essel and Silor in 1972. Essilor now operates in over 100 countries over five continents. Its activities are largely focused on research and development. It is the world's largest manufacturer of ophthalmic lenses.