Extremely corrosive in nature, potassium hydroxide is highly reactive towards acids. On a large scale, it is prepared through the chloralkali process. Available in multiple grades, potassium hydroxide can be used interchangeably with sodium hydroxide (NaOH), although NaOH is preferred in industrial applications because of its lower cost.

Potassium hydroxide is commonly used to manufacture soft and liquid soaps by saponification. Chemical manufacturing, fertilizer production, petroleum refining, and cleaning solutions also rely on potassium hydroxide. In the laboratory, many potassium salts, carbonate, cyanide, permanganate, phosphate, and various silicates are prepared by neutralization reactions involving KOH. A strong alkali, potassium hydroxide is available in both liquid and dry forms.

Common uses of potassium hydroxide are:

• As cleaning agent in the production of liquid soaps and drain cleaners
• In the production of alkaline batteries
• As a chemical intermediate for dyes, pharmaceuticals, and photographic chemicals

A strong and corrosive base, potassium hydroxide can cause serious injury to skin and eyes through absorption. Ingestion and inhalation should also be avoided. To avoid prolonged, damaging exposure to the chemical, workers should wear proper personal protective equipment (PPE) and should handle the chemical in a fume hood. Potassium hydroxide is air sensitive and should be stored in a tightly closed container away from strong acids, strong oxidizing agents, and organic materials.