Potassium hydroxide (KOH), also known as caustic potash, is an inorganic compound with the chemical formula KOH. It is a strong base that exists in solid form as white, hygroscopic, odorless crystals. Potassium hydroxide dissolves in water under strong heat development and forms a colorless, alkaline solution.

Pure potassium hydroxide is used in laboratories and industrial processes where the highest purity is required. Applications of potassium hydroxide include the production of soaps, detergents and cleaning agents, as well as in electrolysis for the production of hydrogen and oxygen. In the food industry, it is used as a food additive (E525) to regulate the pH value or to act as a stabilizer. In the chemical industry, potassium hydroxide is used to neutralize acids and produce potassium salts.

In laboratories, potassium hydroxide can be used to titrate acids and produce buffers. It is also used in organic synthesis as a base to carry out reactions such as aldol reactions or esterifications.