OpenAI has released GPT-5.1, the latest version of its language model that aims to improve ChatGPT’s performance and interaction quality. The update includes two versions: GPT-5.1 Instant and GPT-5.1 Thinking, both designed to handle user queries more effectively.
According to OpenAI, GPT-5.1 Instant offers smoother and more accurate responses while following user instructions more closely. On the other hand, GPT-5.1 Thinking is built to perform faster on simple tasks and maintain consistency during longer or complex interactions. ChatGPT will automatically select the model best suited to respond to each query. Both versions are expected to roll out to users over the coming week. The earlier GPT-5 models will remain accessible for three months under the legacy model menu before being phased out.
ChatGPT’s Customisation Features
As part of this update, OpenAI has expanded ChatGPT’s personality presets. Users can now choose from eight conversational styles - Default, Professional, Friendly, Candid, Quirky, Efficient, Nerdy, and Cynical. These presets allow users to adjust the model’s tone based on context and purpose. The company has also begun testing a new feature that enables direct fine-tuning of ChatGPT’s communication style through settings, which will gradually become available to select users.
OpenAI’s Applications CEO, Fidji Simo, stated in a Substack post that with over 800 million ChatGPT users, customisation has become essential. She emphasised that a single conversational tone can no longer meet the diverse needs of the growing user base.
Users’ Feedback and Competition
The GPT-5 update, launched in August, received mixed reactions, with some users expressing disappointment over the limited improvements compared to earlier models. Following user feedback, OpenAI restored GPT-4o as an available option shortly after GPT-5’s launch.
Meanwhile, OpenAI’s strategic partner Microsoft has reportedly explored alternatives from Anthropic, which are integrating those models into tools like Copilot Researcher, GitHub Copilot, Copilot Studio, and a new Office Agent for Word and PowerPoint automation.
Lastly, the release of GPT-5.1 follows OpenAI’s recent launch of ChatGPT Atlas, an AI-powered web browser with an “agent mode.” This feature is currently only available to ChatGPT Plus and Pro subscribers, and it offers users the ability to perform browser tasks via direct AI actions. The company said GPT-5.1’s rollout marks another step toward improving user experience and flexibility across its growing AI ecosystem.