Patent ID: 8374516

Claim:
An image forming apparatus that has a developing section that is used for developing an electrostatic latent image with a developer; an accommodating section that accommodates the developer; and a supplying section that makes the accommodating section be installed exchangeably, receives the developer from the accommodating section and supplies the developer to the developing section, comprising: a space amount obtaining section that obtains a total amount of volumetric space where the developer does not exist in the supplying section before exchanging the accommodating section; an initial amount calculating section that calculates an initial amount of developer in the accommodating section after the accommodating section is exchanged and developer whose amount corresponds to the total amount of volumetric space is supplied from the accommodating section on the basis of the obtained total amount of volumetric space and a total accommodating amount of the accommodating section; a use amount calculating section that calculates a use amount of the developer used by the developing section; a judging section that judges an existence/inexistence of the developer in the accommodating section on the basis of the initial amount and the use amount that have been calculated; and an informing section that informs a user of a judgment result when the judging section judges that the developer does not exist in the accommodating section.