OpenAI launches GPT-5.1, with two variants: Instant and Thinking, each having significant improvements over GPT-5.

OpenAI has announced the launch of version GPT-5.1 of the language model that underpins ChatGPT, just three months after the debut of GPT-5. This update includes two variants: GPT-5.1 Instant, which is warmer, smarter, and better at following instructions, and GPT-5.1 Thinking, which stands out for its ease of understanding, speed in simple tasks, and persistence in solving complex problems. ChatGPT will automatically select the most suitable model based on user queries. The two variants will be available this week, and GPT-5 will remain active for three months.

Additionally, OpenAI has expanded the list of personalities available for ChatGPT, including options such as Professional, Friendly, Honest, Eccentric, Efficient, Nerdy, and Cynical. ChatGPT has recently surpassed 800 million users, and OpenAI has also launched a web browser called Atlas.