OpenAI released GPT-5.1 Instant and GPT-5.1 Thinking with updates to conversational style and reasoning capabilities.
The updates begin rolling out today to paid users before expanding to free accounts.
OpenAI says this release addresses feedback from users who want AI that feels more natural to interact with, while also improving intelligence.
What’s New
GPT-5.1 Instant
GPT-5.1 Instant, ChatGPT’s most-used model, now defaults to a warmer, more conversational tone.
OpenAI reports improved instruction following, with the model more reliably answering the specific question asked rather than drifting into tangents.
GPT-5.1 Instant can use adaptive reasoning. The model decides when to think before responding to challenging questions, producing more thorough answers while maintaining speed.
GPT-5.1 Thinking
The advanced reasoning model adapts thinking time more precisely. On a representative distribution of ChatGPT tasks, GPT-5.1 Thinking runs roughly twice as fast on the fastest tasks and roughly twice as slow on the slowest tasks compared to GPT-5 Thinking.
Responses use less jargon and fewer undefined terms, which OpenAI says should make the most capable model more approachable for complex workplace tasks and explaining technical concepts.
Customization Options
OpenAI refined personality presets to better reflect common usage patterns. Default, Friendly (formerly Listener), and Efficient (formerly Robot) remain with updates, and new options include Professional, Candid, and Quirky.
These presets apply across all models. The original Cynical (formerly Cynic) and Nerdy (formerly Nerd) options remain available under the same personalization menu.
Beyond presets, OpenAI is experimenting with controls that let you tune specific characteristics such as response conciseness, warmth, scannability, and emoji frequency from personalization settings.
Personalization changes now take effect across all chats immediately, including ongoing conversations. Previously, changes only applied to new conversations started afterward.
The updated GPT-5.1 models also adhere more closely to custom instructions, giving you more precise tone and behavior control.
Rollout Timeline
GPT-5.1 Instant and Thinking begin rolling out today starting with paid subscribers. Free and logged-out users will get access afterward.
Enterprise and Education customers get a seven-day early access toggle to GPT-5.1 (off by default). After that window, GPT-5.1 becomes the default ChatGPT model.
GPT-5 (Instant and Thinking) remains available in the legacy models dropdown for paid subscribers for three months, giving people time to compare and adapt.
Why This Matters
GPT-5.1 can change how your day-to-day workflows behave. Better instruction following means less prompt tweaking and fewer off-brief outputs.
Adaptive reasoning may make simple tasks feel faster while giving more complex work, like technical explanations or data analysis, extra time.
Looking Ahead
OpenAI frames this update as a step toward personalized AI that adapts to individual preferences and tasks.
Updated personality styles and tone options roll out today. Granular characteristic tuning will roll out later this week as an experiment to a limited number of users, with further changes based on feedback.
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