Isobutanol (IUPAC nomenclature: 2-methylpropan-1-ol) is an organic compound with the formula (CH₃)₂CHCH₂OH (sometimes represented as i-BuOH). This colorless, flammable liquid with a characteristic smell is mainly used as a solvent. Its isomers, the other butanols, include n-butanol, 2-butanol, and tert-butanol, all of which are important industrially.