An image forming apparatus includes a plurality of developing devices. Each developing devices performs an electrophotographic process to form an image. The image forming apparatus comprises a first developing device and a second developing device. The first developing device holds a black developer containing a first black coloring agent. The second developing device holds a gray developer. The gray developer contains a second black coloring agent and a coloring agent of a chromatic color. The chromatic color is a complementary color to the second black coloring agent.