OpenAI Rolls Out GPT-5.1 With Smarter, Warmer Chat

OpenAI has announced the rollout of GPT-5.1 that the company promises is more conversational and warmer by default.

The upgrade packs in more intuitive and effective controls "so ChatGPT can better match the tone users want in responses," OpenAI said.

"We're upgrading GPT-5 while making it easier to customise ChatGPT. Starting to roll out today to everyone, beginning with paid users," it said in a blogpost. According to OpenAI, GPT-5.1 improves on both intelligence and communication style.

It has two variants, the GPT-5.1 Instant, ChatGPT's most used model, that is now warmer by default, more conversational, and better at following instructions; and GPT-5.1 Thinking, the advanced reasoning model, that the company promises is easier to understand, faster on simple tasks, and more persistent on complex ones.

GPT-5.1 Thinking offers responses that are clearer, with less jargon and fewer undefined terms, OpenAI said. In a post on X, OpenAI Co-Founder and CEO Sam Altman said "GPT-5.1 is out! It's a nice upgrade".

Altman added that he particularly likes improvements in instruction following and the adaptive thinking. "The intelligence and style improvements are good too," Altman wrote.

OpenAI has made it easier to customise ChatGPT, he said, pointing out that users can pick from presets (default, friendly, efficient, professional, candid, or quirky), even tune it themselves.