OpenAI has rolled out GPT 5.1, an upgraded model for ChatGPT users, promising warmer conversations and improved reasoning. The update comes three months after the launch of GPT 5.
CEO Sam Altman announced the launch of GPT 5.1 on X, calling it a "nice upgrade."
"I particularly like the improvements in instruction following and the adaptive thinking. The intelligence and style improvements are good too," he wrote.
Features of GPT 5.1
The latest version comes in two variants - GPT 5.1 Instant and GPT 5.1 Thinking. While Instant focuses on warmer, intelligent, and more natural conversations, Thinking is built for complex reasoning tasks, and it is easier and faster to understand.
One of the major highlights of the update is the new customisation feature. OpenAI has made it easier for users to personalise how ChatGPT sounds and responds. Users can now choose from six preset personality styles: Default, Friendly, Efficient, Professional, Candid, or Quirky.
For those who want even more control, ChatGPT also allows manual tuning, so users can fine-tune the tone, warmth, and level of detail in responses.
Another highlight is that it has become better at following instructions, which means it will now understand and respond more accurately to what users ask.
"For the first time, GPT‑5.1 Instant can use adaptive reasoning to decide when to think before responding to more challenging questions, resulting in more thorough and accurate answers, while still responding quickly," the company wrote in its blog post.
GPT-5.1 Thinking now gives clearer, more user-friendly answers. The latest model also uses less technical jargon and avoids vague or undefined terms that might confuse readers.
"This makes our most capable model more approachable and easily understandable, especially for complex tasks at work and explaining technical concepts," the company wrote.
When will GPT 5.1 be launched?
OpenAI's GPT‑5.1, both Instant and Thinking variants, begins rolling out today, November 13. The update is first available to paid users on plans like Pro, Plus, Go, and Business. Free and logged-out users will get access in the following days.
For Enterprise and Edu plans, there is a seven-day early-access toggle (off by default), allowing these users to try the new models before general availability. After this period, GPT‑5.1 will become the default model for all users. Paid users on GPT‑5 Pro will also see an upgrade to GPT‑5.1 Pro soon.
