Isopropyl alcohol (IUPAC name propan-2-ol and also called isopropanol or 2-propanol) is a colorless, flammable, organic compound with a pungent alcoholic odor.

Isopropyl alcohol, an organic polar molecule, is miscible in water, ethanol, and chloroform, demonstrating its ability to dissolve a wide range of substances including ethyl cellulose, polyvinyl butyral, oils, alkaloids, and natural resins. Notably, it is not miscible with salt solutions and can be separated by adding sodium chloride in a process known as salting out. It forms an azeotrope with water, resulting in a boiling point of 80.37 °C and is characterized by its slightly bitter taste. Isopropyl alcohol becomes viscous at lower temperatures, freezing at −89.5 °C, and has significant ultraviolet-visible absorbance at 205 nm. Chemically, it can be oxidized to acetone or undergo various reactions to form compounds like isopropoxides or aluminium isopropoxide. As an isopropyl group linked to a hydroxyl group (chemical formula (CH₃)₂CHOH) it is the simplest example of a secondary alcohol, where the alcohol carbon atom is attached to two other carbon atoms. It is a structural isomer of propan-1-ol and ethyl methyl ether. They all have the formula C₃H₈O.