OpenAI updates ChatGPT with GPT 5.1 models, new personalities: What's new

GPT-5.1 introduces a warmer, more conversational Instant model and a smarter Thinking model, while adding new personality presets and tone-tuning options for a more personalised ChatGPT experience

OpenAI has announced its new GPT-5.1 AI models, introducing two upgraded options: GPT-5.1 Instant and GPT-5.1 Thinking. The company says the latest versions aren’t just more capable — they also have more personality, with GPT-5.1 Instant described as “warmer” and more naturally conversational, while GPT-5.1 Thinking is positioned as the advanced reasoning model.

 

Alongside the new models, OpenAI is also expanding ChatGPT’s personality controls, letting users fine-tune how the chatbot sounds and responds based on a broader list of preset styles. The company noted that people prefer different chat styles depending on context, and it’s now offering more ways to customise that experience.

GPT 5.1 models: What is new

GPT-5.1 Instant is designed to be the everyday model for most users. OpenAI says it’s better at conversational flow, more responsive to instructions, and capable of deciding when it should “think before answering” based on the complexity of a query. The idea is simple: fast replies for easy questions, and more deliberate responses when things get complicated.

 

  GPT-5.1 Thinking, on the other hand, is built for deeper reasoning tasks. It’s trained to better manage how much time it spends analysing a problem — answering simple prompts more quickly and taking longer only when required. The model is also said to produce clearer, more concise explanations with less technical jargon than previous versions.

GPT 5.1 models: Availability

GPT-5.1 is rolling out starting today to Pro, Plus, Go, and Business users. Free and logged-out users will get access over the next few days. Enterprise and Education customers will have a seven-day early-access toggle before the update becomes the default.

 

  OpenAI added that the rollout is gradual, so availability may vary by user. The company also confirmed that GPT-5 Pro will soon be upgraded to GPT-5.1 Pro.

ChatGPT personalities: What is new

A notable addition is OpenAI’s expanded list of ChatGPT personality presets. These allow users to tailor how ChatGPT sounds, ranging from professional to playful. There are eight styles available:

• Default 
• Friendly (formerly Listener) 
• Efficient (formerly Robot)
• Professional (New)
• Candid (New)
• Quirky (New)
• Cynical (formerly Cynic)
• Nerdy (formerly Nerd)

OpenAI is also testing deeper personalisation options that will let users adjust characteristics like how concise, warm or structured the responses should be, along with controls for emoji usage. These fine-tuning features are rolling out as an experiment to a limited group of users later this week.

 

The updated tone and style presets begin rolling out today.