Potassium hydroxide  is an inorganic compound with the formula KOH, and is commonly called  caustic potash .

Along with sodium hydroxide (NaOH),  KOH  is a prototypical strong base. It has many industrial and niche applications, most of which exploit its caustic nature and its reactivity toward acids. An estimated 700,000 to 800,000 tonnes were produced in 2005.  KOH  is noteworthy as the precursor to most soft and liquid soaps, as well as numerous potassium-containing chemicals. It is a white solid that is dangerously corrosive.

KOH  exhibits high  thermal stability . Because of its high stability and relatively low  melting point , it is often melt-cast as pellets or rods, forms that have low surface area and convenient handling properties. These pellets become tacky in air because KOH is  hygroscopic . Most commercial samples are ca. 90% pure, the remainder being water and carbonates.  Its  dissolution  in water is strongly  exothermic . Concentrated aqueous solutions are sometimes called potassium  lyes . Even at high temperatures, solid KOH does not dehydrate readily.

1. Used as a desiccant and absorbent, used to make oxalic acid and various potassium salts, also used in electroplating, carving, lithography, etc.

2. Mainly used as raw material for potassium salt production, such as potassium permanganate and potassium carbonate.

3. Basic chemical raw materials, used in medicine, daily chemical industry, etc.

4. Used as analytical reagent, saponification reagent, carbon dioxide and water absorbent

5. The daily chemical industry is used as a raw material for the manufacture of washing soap, shampoo soft soap, vanishing cream, cold cream and shampoo. The pharmaceutical industry is used to produce progesterone, vanillin and other raw materials. The dye industry is used to manufacture melamine dyes. Used in the manufacture of alkaline batteries in the battery industry.