OpenAI on Thursday announced the GPT 5.1 models of ChatGPT, which promise to be “enjoyable to talk to”, in addition to being smarter than their predecessor.
The GPT 5.1 series for ChatGPT involves two models—GPT‑5.1 Instant, which is the model for regular use, and GPT‑5.1 Thinking, which is the advanced reasoning model.
This follows hundreds of users demanding that one of the world’s most popular AI chatbots be made more human and conversational, the AI giant said in a statement.
“Weird that they didnt include a single benchmark,” a Redditor wrote, highlighting an interesting change from OpenAI’s previous announcements, in which it used a lot of statistics to prove that the new model was the best.
Instead, OpenAI seems to have focused on user feedback more this time.
The AI giant claims that ChatGPT 5.1 was developed with these comments in mind: the chatbot’s default tone will now be warmer and more empathetic. Still, users are also given the option to select their favourite personality style from a list of preset options, some of which were released earlier this year.
The OpenAI statement also compares how the two models—ChatGPT 5.1 and ChatGPT 5—think and process data before responding to user queries.
It says that the newest model processes (‘thinks’) two times faster for the fastest tasks (easier queries) and two times slower on the slowest tasks (tougher queries), meaning that your simpler questions to the chatbot will get faster replies, while your complex questions to the chatbot will get thorough answers, OpenAI said.
It also said that ChatGPT 5.1’s responses were “clearer, with less jargon, and fewer undefined terms”.
“GPT‑5.1 Instant and Thinking begin rolling out today, starting with paid (Pro, Plus, Go, Business) users and then to free and logged-out users. Enterprise and Edu plans get a seven-day early-access toggle (off by default). After that window, GPT‑5.1 will become the sole default model,” the statement said.
“We’re bringing both GPT‑5.1 Instant and GPT‑5.1 Thinking to the API later this week. GPT‑5.1 Instant will be added as gpt-5.1-chat-latest, and GPT‑5.1 Thinking will be released as GPT‑5.1 in the API, both with adaptive reasoning,” the statement added.
“Maybe their weirdest model release ever? Why the rush?” a Redditor questioned.
“Hopefully context window is big,” another Redditor wrote.
“Probably a response to 4.5 Sonnet. That model is far more warm, personable, and ‘real’ than 5 instant was. Made me prefer it for general chats and life advice. We’ll see if this 5.1 stands up,” a third Redditor noted.
