OpenAI’s GPT-5.1 adds personality presets and smarter chat

OpenAI has introduced GPT-5.1, a major update to the GPT-5 model it released in August, promising a smarter and more pleasant ChatGPT experience. The company says GPT-5.1 makes conversations clearer, warmer, and more reliable while keeping the service easy to use for hundreds of millions of people who rely on it every month.

The update arrives in two main versions: GPT-5.1 Instant and GPT-5.1 Thinking. Instant is designed to feel warmer and more responsive than the earlier GPT-5 Instant, with stronger reasoning and better ability to follow instructions. Thinking is built for tougher work, and OpenAI says it is now easier to understand everyday questions while staying more focused and persistent on complex tasks. In most cases, ChatGPT will route questions automatically to the version that seems best suited to answer. The new models begin rolling out to users this week, while the older GPT-5 options will stay in a legacy menu for about three months before being retired.

Alongside the new models, OpenAI is expanding how people can shape the tone of their AI assistant. ChatGPT now offers a broader set of personality presets, including Default, Professional, Friendly, Candid, Quirky, Efficient, Nerdy, and Cynical. The company is also testing new controls in settings that let some users fine-tune ChatGPT’s style even more directly, an experiment that will reach a portion of the user base this week. OpenAI executive Fidji Simo wrote that with more than 800 million people using ChatGPT, it is no longer realistic to expect one style to fit everyone.

GPT-5.1 also arrives after a mixed reception for GPT-5. Despite heavy promotion ahead of its launch, many users saw the earlier release as only a small step forward and were unhappy that it became the default model. The reaction pushed OpenAI to quickly restore GPT-4o as an option. Microsoft, OpenAI’s key partner, has also explored more use of rival Anthropic’s models, which now help power several Copilot products and a new Office Agent that can draft Word and PowerPoint files. The GPT-5.1 release comes only weeks after OpenAI rolled out ChatGPT Atlas, an AI-powered web browser with an agent mode that can perform actions in the browser for Plus and Pro subscribers.