Producer gas is fuel gas that is manufactured by blowing a coke or coal with air and steam simultaneously. It mainly consists of carbon monoxide (CO), hydrogen (H₂), as well as substantial amounts of nitrogen (N₂). The caloric value of the producer gas is low (mainly because of its high nitrogen content), and the technology is obsolete. Improvements over producer gas, also obsolete, include water gas where the solid fuel is treated intermittently with air and steam and, far more efficiently synthesis gas where the solid fuel is replaced with methane.

In the USA, producer gas may also be referred to by other names based on the fuel used for production such as wood gas. Producer gas may also be referred to as suction gas. The term suction refers to the way the air was drawn into the gas generator by an internal combustion engine. Wood gas is produced in a gasifier