OpenAI has introduced GPT-5.1, an update to its GPT-5 model, aiming to deliver faster responses, improved reasoning, and more flexible conversational controls as the company works to refine its ChatGPT experience for both consumer and enterprise users.
The release includes new Instant and Thinking variants designed to offer more adaptive reasoning and a broader range of personalization options, the company said in a blog post.
GPT-5.1 is available across ChatGPT’s free and paid tiers, with enterprise and education customers receiving a brief early-access period before it becomes the default model. OpenAI said the models are also accessible through the API.
In a separate Substack post, OpenAI CEO for Applications, Fidji Simo, said these chat models are “trained using the same stack as our reasoning models,” adding that they “score higher on factuality and complex problem-solving than GPT-5, while also introducing a more natural, conversational tone.”
