Imagen 4 goes dark on 17 August — and the replacement is not a drop-in swap

Google is switching off Imagen 4 on 17 August 2026. The company announced the deprecation in the Gemini API changelog on 15 June 2026, naming all three generally available endpoints: `imagen-4.0-generate-001`, `imagen-4.0-fast-generate-001` and `imagen-4.0-ultra-generate-001`. After that date they stop answering. The shutdown closes a short life. Imagen 4 reached general availability in 2025 as Google's dedicated text-to-image family, split into a fast, a standard and a quality-first Ultra tier. Its successor is not another Imagen: image generation has moved into the Gemini line itself, to the models the public knows as Nano Banana 2 and Nano Banana Pro. That is what makes this retirement different from a routine version bump. Imagen 4 was called through a dedicated image-generation method; the Gemini image models are called through the same general content-generation method used for text. Anyone still on the old endpoints is not editing a model name in a config file — they are rewriting the call. The date is worth marking for a second reason. On the enterprise side of Google's stack the same Imagen 4.0 endpoints were already deprecated earlier, so teams may have met two different cut-off dates for what looks like one model. Where a service is being wound down on different platforms at different speeds, the only reliable date is the one published by the vendor for the platform actually being used.