A disclosed image forming apparatus for forming an image on a recording medium includes an inkjet head having a nozzle surface and inkjet nozzles on the nozzle surface and configured to jet ink droplets from the inkjet nozzles; a recording medium conveying mechanism including a recording medium conveyor and configured to convey the recording medium by the recording medium conveyor into an image forming area facing the inkjet head; a test pattern forming part provided separately from the recording medium conveyor; a control unit configured to perform an image forming test where a test pattern is formed on the test pattern forming part by jetting ink droplets from the inkjet head; and a test pattern detection unit configured to detect the test pattern formed on the test pattern forming part.