Precursor to other potassium compounds
Many potassium salts are prepared by neutralization reactions involving KOH. The potassium salts of carbonate, cyanide, permanganate, phosphate, and various silicates are prepared by treating either the oxides or the acids with KOH. The high solubility of potassium phosphate is desirable in fertilizers.

Manufacture of soft soaps
The saponification of fats with KOH is used to prepare the corresponding potassium soaps. Such soaps tend to be more soluble and are found in liquid soaps. The more common sodium soaps are more easily solidified.[8]

As an electrolyte
Aqueous potassium hydroxide is employed as the electrolyte in alkaline batteries based on nickel-cadmium and manganese dioxide-zinc. Potassium hydroxide is preferred over sodium hydroxide because its solutions are more conductive.[9]

Niche applications
KOH attracts numerous specialized applications, but virtually all capitalize on its basic or degradative properties. KOH is widely used in the laboratory for the same purposes. In chemical synthesis, the selection of KOH vs. NaOH is guided by the solubility for the resulting salt. Its corrosivity is sometimes used in cleaning and disinfection of resistant surfaces and materials.[10] It is often the main active ingrediant in chemical "cuticle removers."