OpenAI has just launched a significant upgrade to the engine that powers ChatGPT, introducing GPT-5.1 and promising a breakthrough in how the AI interacts with users. This new release focuses on making the models both more intelligent and dramatically more enjoyable, reliable, and personalised to your unique style.
SMART AND FRIENDLY: A NEW AI ERA
The update brings two powerful new versions: GPT-5.1 Instant and GPT-5.1 Thinking. The Instant model, which is the version most people use, is now notably warmer and more conversational by default, often displaying a surprisingly playful tone while staying accurate. Crucially, it’s also much better at reliably following the exact instructions you give it.
Meanwhile, the advanced GPT-5.1 Thinking model has been made more efficient. It now spends less time on simple requests while dedicating more time and effort to complex challenges. This means users get quicker answers for easy questions and more comprehensive, thorough responses for difficult tasks, all delivered in clearer language, with less technical jargon.
CUSTOMISE YOUR EXPERIENCE
OpenAI recognises that everyone has different preferences for how their AI should sound, leading to a huge boost in personalisation options. Users can now tailor ChatGPT’s tone with new, intuitive style presets. Beyond the existing options, new presets like Professional, Candid, and Quirky are rolling out today, making it quick and easy to select a personality that fits the current conversation.

Added to this, the company is experimenting with even more granular controls, allowing some users to directly fine-tune specific characteristics in their settings, such as how concise or warm the AI’s responses are, or how frequently it uses emojis.
HOW TO GET THE UPGRADE
The new GPT-5.1 models are already rolling out, starting with paid ChatGPT users (Plus, Pro, Go, and Business subscribers). Free and logged-out users will receive the update shortly thereafter. The update is applied gradually, so while some users will see the benefits right away, it may take a few days to reach everyone to ensure performance remains stable. With the improved models and deep customisation features, your next chat with the AI should feel not just smarter, but genuinely tailored to you.

