In a significant move to enhance user interaction with artificial intelligence, OpenAI announced the rollout of its new GPT-5.1 models on Thursday, 13 November. The Sam Altman-led company introduced two distinct upgraded versions for its popular chatbot, ChatGPT: GPT-5.1 Instant and GPT-5.1 Thinking. In an official blog post, OpenAI stated that these models are not only more intelligent but also designed to be more enjoyable to converse with.
What's New in GPT-5.1 Instant and GPT-5.1 Thinking?
The core of this update lies in the specialized capabilities of the two new models. OpenAI has designed them to cater to different user needs, making the ChatGPT experience more personalized and effective than ever before.
GPT-5.1 Instant: Warmer and More Responsive
OpenAI describes the GPT-5.1 Instant model as inherently "warmer" and more conversational. As the most widely used model, it has been fine-tuned to be highly responsive to user instructions, ensuring a smooth and natural conversational flow. The company revealed that based on early testing, this version often surprises users with its playful nature while maintaining clarity and usefulness. A key advancement is its ability to autonomously decide when to "think before responding" to more challenging queries, aiming to deliver accurate answers without sacrificing speed.
GPT-5.1 Thinking: Master of Complex Reasoning
On the other end of the spectrum is GPT-5.1 Thinking, which is engineered for tasks requiring deeper reasoning and analysis. This model is trained to manage its thinking time intelligently, dedicating more processing power to complex problems while still providing swift responses to simpler prompts. Furthermore, it generates clearer responses with less technical jargon and fewer undefined terms compared to its predecessors. This makes it an ideal tool for handling intricate work assignments and explaining sophisticated technical concepts in an accessible manner.
Enhanced Personalization: Control Your Chatbot's Tone
Alongside the new model architectures, OpenAI is rolling out major personalization features. Users can now actively adjust the AI's tone and style to better match their preferences. The platform offers eight distinct style presets:
- Default
- Friendly (previously known as Listener)
- Efficient (formerly Robot)
- Professional
- Candid
- Quirky
- Cynical (previously Cynic)
- Nerdy (formerly Nerd)
For users seeking even more precise control, OpenAI is experimenting with advanced fine-tuning options. These experimental settings, launching later this week for a limited user group, will allow individuals to calibrate characteristics such as how concise, warm, or scannable the responses are, and even control the frequency of emoji usage.
Availability and Rollout Schedule
The deployment of the new GPT-5.1 models began on 13 November. The rollout is being conducted in a phased manner. Initially, access is being granted to paid subscribers, including those on the Pro, Plus, Go, and Business plans. Free and logged-out users will gain access over the subsequent few days.
Notably, customers on Enterprise and Edu plans will receive a special seven-day early-access toggle, allowing them to test the new models before the update becomes the sole default option. OpenAI also confirmed that the existing GPT-5 Pro version will soon be upgraded to GPT-5.1 Pro. The company emphasized that the rollout is gradual, so availability might vary from user to user initially.
