Duplex printing

Duplex printing is a feature of some computer printers and multi-function printers (MFPs) that allows the printing of a sheet of paper on both sides automatically. Print devices without this capability can only print on a single side of paper, sometimes called single-sided printing or simplex printing.

Consumer and low-to-medium volume office printers use a duplexing unit that reverses a piece of paper after the first side has been printed. Duplex multifunction printers that also support duplex scanning have a reversing automatic document feeder (RADF) for scanning both sides. Higher volume printers may effectively have two print engines in a single device, and are able to print both sides of the paper in a single pass.