Acetone is the organic compound with the formula (CH3)2CO, a colorless, mobile, flammable liquid, the simplest example of the ketones.

Acetone is miscible with water and serves as an important solvent in its own right, typically as the solvent of choice for cleaning purposes in the laboratory. About 6.7 million tonnes were produced worldwide in 2010, mainly for use as a solvent and production of methyl methacrylate and bisphenol A. It is a common building block in organic chemistry. Familiar household uses of acetone are as the active ingredient in nail polish remover and as paint thinner.

About a third of the world’s acetone is used as a solvent, and a quarter is consumed as acetone cyanohydrin a precursor to methyl methacrylate. In the composites industry Acetone is used to clean fibreglass tools after hand lamination and dissolving two-part epoxies and superglue before hardening.