Polyethylene glycol cetyl ether (polyethylene glycol hexadecyl ether) is a nonionic surfactant produced by the ethoxylation of cetyl alcohol to give a material with the general formula HO(C<sub>2</sub>H<sub>4</sub>O)<sub>n</sub>C<sub>16</sub>H<sub>33</sub>. Several grades of this material are available depending on the level of ethoxylation performed, with repeat units (n) of polyethylene glycol varying between 2 and 20. Commercially it can be known as Cetomacrogol 1000, Brij 58 (when n=20), Brij 56 (when n=10), and other trade names.
It is used as a solubilizer and emulsifying agent in foods, cosmetics, and pharmaceuticals, often as an ointment base. It is used as an oil in water (O/W) emulsifier for creams/lotions, and a wetting agent.