OpenAI quietly confirmed that the last GPT‑4‑based model still accessible to ChatGPT users, GPT‑4.5, will be retired later this year. The announcement appeared as a short note in the platform’s release notes, stating, “Today, we’re continuing to retire older models with limited usage in ChatGPT so we can better serve our newer, most capable models.” No fanfare accompanied the decision, but the impact is unmistakable.

According to the same notice, GPT‑4.5 will cease to be available on June 27, 2026 after a 30‑day sunset period. The older o3 model, a pure‑reasoning variant, follows suit on August 26, 2026 after a 90‑day phase‑out. Both models are currently limited to paid ChatGPT subscribers who can select them in the app’s model settings.

For many, the retirement feels like the loss of a familiar personality. On X, users voiced frustration, with one commentator, Striver, writing, “To this day, 4.5 is the best writing model. o3 was a native pure reasoning model. 5 series still doesn’t match what those two had.” The sentiment underscores how deeply users connected with the quirks and capabilities of these versions.

GPT‑4 and its offshoots, especially GPT‑4o, were the first models to demonstrate that AI could handle essays, exams, code, and image analysis with a level of competence that sparked both excitement and anxiety across the tech world. They turned AI from a novelty into a tool people relied on daily.

When OpenAI introduced ChatGPT‑5, it triggered a backlash that briefly forced the company to restore GPT‑4o for a limited window before finally ending its availability. That episode highlighted a new kind of nostalgia: users missing not just functionality but the distinct “personality” of earlier models.

Now, with GPT‑4.5’s departure, no GPT‑4 variants remain in ChatGPT’s lineup. OpenAI’s strategy appears to bet that users will quickly adopt newer models like GPT‑5.5, which promise higher benchmarks, faster responses, and broader capabilities. Yet the reaction to earlier retirements suggests that emotional attachment may linger, even as technology races forward.

The retirement marks the close of a chapter that reshaped how millions interact with artificial intelligence. While the next generation will likely eclipse the old in raw performance, the legacy of GPT‑4’s blend of competence and character will remain a touchstone for the industry.

This article was written with the assistance of AI.
News Factory SEO helps you automate news content for your site.