Potassium perchlorate (KClO4) is an inorganic substance belonging to the perchlorate family of salts. It is typically found as a crystalline, colorless solid and is used in numerous industrial applications. KClO4 is manufactured by the reaction of KCl with sodium perchlorate. Potassium perchlorate is a strong oxidizer and creates an explosive force on reaction with organic compounds (carbon-containing compounds such as sugars and plastics). It is primarily used in the manufacture of explosives for its strong reactive force.

Potassium perchlorate is used as an antithyroid agent for the treatment of hyperthyroidism, the condition that results when the thyroid gland produces an excessive amount of hormones (thyroxine and triiodothyronine). Hyperthyroidism excites various systems of the body with a result resembling an adrenaline overdose. It overstimulates metabolism, increases the heart rate, causes anxiety and tremors and results in diarrhea and weight loss. Potassium perchlorate acts upon the overstimulated thyroid hormones to bring the system back to equilibrium.

Potassium perchlorate is a potent oxidizing agent that spontaneously reacts with many naturally occurring substances. An oxidizing agent, or oxidizer, is a substance that transfers oxygen atoms to its reactant, therefore stimulating the combustion (burning) of organic materials. Its oxidizing properties are used in the manufacture of fireworks, safe matches, rocket propelling agent, signal flares and explosives.

Potassium perchlorate is popularly used as a disinfectant, an agent that inhibits, neutralizes or destroys harmful microorganisms. Potassium perchlorate has the ability to sterilize by destroying microbic life.

Potassium perchlorate is used as a rocket propellant. A propellant is a fuel used by rockets for propulsion. Typical rocket propellants include paraffin, kerosene, liquid hydrogen and alcohol. Propellants require an oxidizing agent to burn them and provide thrust. Potassium perchlorate makes a good rocket propellant because it burns at a fast rate, burns without leaving behind dead weight (ash or residue), has a high calorific value (or heating value, i.e., the amount of heat that is released during combustion) that increases the efficiency of fuel and produces large volumes of gases for every gram of fuel combusted.

Potassium perchlorate is used to make protective breathing equipment used in fighter aircrafts in the event of depressurization. Other uses include electronic tubes, nuclear reactors, additives for lubricating oils, rubber manufacture, aluminum refining, as a fixer in dyes and for fabrics, in finishing leather and tanning, in electroplating and the production of enamels and paints.