An image forming apparatus includes a developing cartridge, a main memory and a controller. The controller is configured to perform determining whether the developing cartridge is reached a lifetime on a basis of: at least one of s developing maximum printable number of sheets which corresponds to developing identification information, a maximum developing roller rotation number which corresponds to the developing identification information, and a maximum dot count which corresponds to the developing identification information; and at least one of a developing cumulative number of printed sheets, a cumulative developing roller rotation number and a cumulative dot count.