OpenAI has once again pressed the upgrade button on its flagship chatbot, and this time, it’s getting a personality. The company has rolled out GPT-5.1, a new version of its model that it promises will make ChatGPT “smarter,” “more conversational,” and better at adapting to your preferred communication style. CEO Sam Altman kept things typically understated, calling it “a nice upgrade,” but under the hood, this is a bigger deal than it sounds. OpenAI says GPT-5.1 isn’t just more capable, it’s also warmer, wittier, and more human in how it talks back, over GPT 5.
OpenAI GPT-5.1: What is new
The GPT-5.1 rollout comes in two flavours — GPT-5.1 Instant and GPT-5.1 Thinking — with paid ChatGPT users getting first dibs starting today.
The “Instant” model is meant to be the everyday engine that most people use. OpenAI describes it as “now warmer, more intelligent, and better at following your instructions.” In other words, the version of ChatGPT you chat with to plan a trip, fix your code, or write a birthday toast is now supposed to sound more natural, and, surprisingly, a little cheekier.
According to the company, testers found themselves taken aback by its newfound “playfulness.” That’s a deliberate choice, OpenAI wants the chatbot to feel less robotic and more like you’re talking to a sharp, helpful colleague who occasionally cracks a joke.
Meanwhile, GPT-5.1 Thinking is the more advanced (and, let’s face it, more serious) sibling, built for users who throw complex or abstract questions at the AI. OpenAI says it’s designed to produce answers that are “easier to understand and faster on simple tasks, more persistent on complex ones.”
It’s also more efficient: the model “burns fewer tokens on basic questions,” saving you time and bandwidth. And when the task gets difficult, like explaining quantum computing to a six-year-old , it promises to deliver responses that are “clearer, with less jargon and fewer undefined terms.”
Even here, OpenAI insists that the Thinking model retains a human touch, describing it as “warmer and more empathetic.” So, yes, the brainier version of ChatGPT will still ask how your day’s going.
Meet ChatGPT’s new moods: Professional, Candid, and Quirky
Beyond the brainpower boost, GPT-5.1 comes with a personality pack. OpenAI is rolling out three new conversation styles, Professional, Candid, and Quirky, which join an already eclectic lineup that includes Default, Friendly (formerly Listener), Efficient (formerly Robot), Cynical (formerly Cynic), and Nerdy (formerly Nerd).
These new styles can be switched in the app’s personalisation settings, giving users more say in how ChatGPT behaves, whether you want it to sound like a polished consultant, a no-nonsense colleague, or that slightly eccentric friend who types in lowercase but always has the best ideas.
The company hinted that this is just the beginning. In a blog post, OpenAI said it’s experimenting with finer-grained control over ChatGPT’s tone and behaviour, eventually allowing users to customise personality traits beyond the preset modes.
“Today’s GPT-5.1 updates and new customisation options are a step toward a ChatGPT that feels like it fits you, smarter, more enjoyable to talk to, and more adaptable to your preferences,” OpenAI said. “Going forward, we’ll continue improving along these dimensions, there’s much more to come.”
That sentiment mirrors how OpenAI’s top brass have been framing the company’s direction lately: the chatbot of the future isn’t just intelligent, it’s individualised. CFO Sarah Friar has described personalisation as “the next big frontier in chatbot technology.”
GPT-5.1: Price and availability
The new model, GPT-5.1, is available to paid users only. However, OpenAI claimed that this will remain true for just 3 months. After that, we expect the new model to come to all, including free users. According to the company, “The GPT-5 sunset period does not affect the availability of other legacy models.” It also said that OpenAI will also be updating GPT-5 Pro to GPT-5.1 soon.
With the new update, OpenAI is trying to address the previous backlash against GPT-5. To recap, during the launch of GPT-5, users claimed that the newer model was not warm enough compared to the GPT-4o model. Now, GPT-5.1 focuses on its personality to make it more warmer and wittier.
