An image forming apparatus includes a developing device including a developer bearing member for bearing and conveying a developer and configured to develop a latent image formed on an image bearing member using the developer, a bias application unit configured to apply at least an AC bias to the developer bearing member, an integration unit configured to integrate an application time of the AC bias applied by the bias application unit, and a determination unit configured to determine a replacement timing of the developing device based on an integrated value by the integration unit.