ChatGPT 5.1 Instant and Thinking announced with better intelligence, advanced reasoning

Back in August, OpenAI announced ChatGPT 5 as its smartest and fastest model, delivering substantial performance leaps across agentic tasks, reasoning and advanced mathematical capability. Now, the company has rolled out GPT 5.1 in two versions: Instant and Thinking, promising better intelligence and advanced reasoning. Continue reading to know more about the GPT 5.1 variants.

Understanding ChatGPT 5.1 variants

OpenAI says that ChatGPT 5.1 has been announced after hearing feedback from users asking AI to be more conversational and not only be just smart. Therefore, the newly unveiled GPT 5.1 brings improvements in two departments: intelligence and communication style.

ALSO READ: How to download and install ChatGPT Atlas web browser: Step-by-step guide

GPT 5.1 Instant is designed to adapt more flexibly to the user’s preferred communication style. With the new tone-control features, users can request a more formal, casual, concise or expressive style as needed. This addresses a long-standing user request for responses that match different contexts, from professional writing to everyday guidance.

GPT 5.1 Thinking, which is built for complex reasoning, can deliver clearer explanations and handle detailed multi-part problems more effectively than before. For simpler queries, it generates faster results. The model is able to stay focused on longer reasoning chains, which helps in areas such as programming, research and planning.

How to access ChatGPT 5.1 Instant / Thinking

Whether you are using ChatGPT through its web version or Android / iOS app, the model selector at the top will show GPT 5.1 Instant and GPT 5.1 Thinking options. If you don’t see these on the web version, you will have to refresh or sign out and sign in again to view them.

On the app, you may need to update to the latest version, and you should be able to see the GPT 5.1 variants. Currently, GPT 5.1 Thinking is not available for Free and Go plans. This could also be the reason you may only see the Instant variant and not the Thinking version. Likely, GPT 5.1 Thinking could be made available a bit later for Free and Go users.

ALSO READ: ChatGPT to stop working on WhatsApp from January 2026, here’s how to save your chats

Have you tried the ChatGPT 5.1 variants? Let us know your experience by posting your comments below.