OpenAI rolls out GPT-5.1 Instant, which is “warmer by default”, and GPT-5.1 Thinking, which is “easier to understand and faster”, starting with paid subscribers

We're upgrading GPT‑5 while making it easier to customize ChatGPT. Starting to roll out today to everyone, beginning with paid users.

OpenAI 2025-11-13

Context & Ripple Effects

This rollout extends OpenAI’s earlier move to expose GPT-5 choices through Auto, Fast, and Thinking settings rather than present a single undifferentiated ChatGPT experience. It makes response style, reasoning behavior, and speed part of the product surface.

The release also became an early step in a rapid Instant-model replacement cycle: GPT-5.3 Instant later emphasized answer accuracy and web-search context, before GPT-5.5 Instant replaced it as ChatGPT’s default.

First-order effects

Paid ChatGPT subscribers are first to receive separate GPT-5.1 Instant and Thinking experiences, with Instant positioned around a warmer default tone and Thinking around clearer, faster outputs.
OpenAI turns GPT-5 customization into a more explicit user-facing choice, reinforcing distinctions between quick-response and reasoning-oriented modes.

Second-order effects

The split raises the bar for competing AI assistants to differentiate not only on model capability but also on controllable tone, clarity, and response latency.
For users and teams, model selection becomes more consequential: the best experience may depend on whether a task values conversational style, speed, or more deliberate reasoning.

Third-order effects

If this release cadence persists, frontier-model competition will increasingly center on continual product tuning and defaults, not just occasional flagship-model launches.
The pattern points toward AI interfaces that route or expose multiple model behaviors for different tasks, making interaction design a durable part of model differentiation.

The trend: Consumer AI is shifting from one-model chatbots toward frequently updated, task- and preference-specific model experiences.

Discussion

@sama Sam Altman on x
GPT-5.1 is out! It's a nice upgrade. I particularly like the improvements in instruction following, and the adaptive thinking. The intelligence and style improvements are good too.
@davidondrej1 David Ondrej on x
GPT 5.1 is the biggest nothing-update I've ever seen.
@businessbarista Alex Lieberman on x
GPT 5.1 is way bigger than people think imho. No this wasn't a model shift like 3.0 to 3.5, but I'd argue we're at a level of intelligence now, where things like personality, adaptive thinking, and custom instructions will have a more profound impact on the average user than
@kimmonismus @kimmonismus on x
A few thoughts on the GPT-5.1 release Either the release was rushed, or OpenAI intends to release more frequently. The website doesn't show any evaluations of the well-known benchmarks compared to GPT-5. The only thing is the reasoning update along with its graph. This could
@slow_developer Haider on x
OpenAI has quietly launched GPT-5.1 GPT-5.1 instant: faster “chatty” default, warmer tone, better instruction-following GPT-5.1 thinking: deeper reasoner with dynamic thinking time: 2x faster on easy tasks, 2x slower on the hardest for better answers feels closer to the GPT-4o
@scaling01 @scaling01 on x
back in my days we would have called GPT-5.1 just GPT-5-2025-11-12 or GPT-5-latest but whatever, if you desperately need the title for smallest improvement in capabilities that has resulted in a change of version number, then here you go
@emollick Ethan Mollick on x
One question I have about GPT 5.1 is whether “personality” biases the model outputs. There is reason to suspect that custom instructions might impact the quality and type of answers that you receive. I would love more information about whether that is still true for personality. …
@mattshumer_ Matt Shumer on x
I've been testing GPT-5.1 for a few days. My quick notes: - creative writing style is a LOT better - it's much faster than GPT-5 (with similar intelligence) for most prompts - the personality is WAY better (but can still sometimes be annoying) - it's great in Codex!
@aidan_mclau Aidan McLaughlin on x
welcome gpt-5.1 instant! 🧠 better than 4o EQ and IQ 🍓 first chat model to use CoT! 🏎️ still just as fast as gpt-5 instant ✅ likely the safest chatbot in the world super proud to have helped train this model with an incredible team
@alexfinn Alex Finn on x
Don't be fooled by the .1, this is a big upgrade Marginally better at coding, a lot better at chat, vibes, and coming up with novel creative ideas In just an hour it came up with 10 improvements for my app no other model has thought of Most creative, fun to talk to model yet
@fidjissimo Fidji Simo on x
GPT-5.1 is a great new model that we think people are going to like more than 5. But with 800M+ people using ChatGPT, one default personality won't work for everyone. We launched new preset personalities so people can make ChatGPT their own. https://fidjisimo.substack.com/ ...
@sama Sam Altman on x
Also, we've made it easier to customize ChatGPT. You can pick from presets (Default, Friendly, Efficient, Professional, Candid, or Quirky) or tune it yourself.
@miles_brundage Miles Brundage on x
Not sure why GPT-5.1 was shipped with various known safety regressions (vs. October) + unfinished work, per the system card addendum? Some of the claims are a bit vague but overall it sounds like the claim is - better than the original GPT-5, but worse than the October version.
@synthwavedd Leo on x
What the fuck lmao they dropped GPT-5.1 out of nowhere with no benchmarks in sight Are they trying to beat someone to the punch
@synthwavedd Leo on x
- no benchmarks - no API release - system card looks sloppy at best and is weirdly short - was planned for late nov maybe their weirdest new model launch ever? why did they randomly rush it out..?
@kimmonismus @kimmonismus on x
Now that GPT-5.1 has been released, Gemini 3.0 is only a matter of hours or days away. I'm pretty sure OpenAI wanted to get ahead of Google's release.
@scaling01 @scaling01 on x
GPT-5.1 looks like an insane nothingburger. Looks like OpenAI will roll out the big guns only next month Where are my benchmarks?
@deredleritt3r Prinz on x
This is actually huge. -57% tokens for easiest questions (better replacement for Google search). +71% juice for hardest questions should provide MUCH better responses. [image]
@deryatr_ Derya Unutmaz on x
I've had early access to GPT-5.1, and it's definitely a great upgrade that feels more intelligent and insightful. Its prose is also delightful, super clear, and more human-like; in fact, for me it is now better than GPT-4.5, which had been the best model for these reasons.
@nearcyan Near on x
@aidan_mclau its kinda insulting to say “likely the safest chatbot in the world” by just citing internal evals and vibes, at least pretend there is a justification and at least add some type of qualifier or im going to put it up against a single state markov chain which is probab…
@apples_jimmy @apples_jimmy on x
Tops the creative writing benchmark, prob biggest thing for me out of the 5.1 release. Now we wait for shipmas.
@aidan_mclau Aidan McLaughlin on x
@nearcyan since gpt5 chat we've probably shipped the safest chat models, the amount of evals and rl we've done is wild, to the point that people found it quite cold the success here is making it a fun model to chat with while maintaining the safety bar we set
@nickaturley Nick Turley on x
1/ GPT-5.1 is starting to roll out today. It brings improvements to how enjoyable ChatGPT feels to talk to, and how well it follows what you're actually asking.
@tszzl Roon on x
👍 [image]
@xiangningchen Xiangning Chen on x
Proud to see this out in the world. Spent quite some time pushing on instruction following and it is exciting to see it land and get recognized. Huge team effort and grateful for everyone who made GPT 5.1 shine! [image]
@tamaybes @tamaybes on x
“I've got you, Ron — that's totally normal, especially with everything you've got going on lately.” Who actually wants their model to write like this? Surprised OpenAI highlighted this in the GPT-5.1 announcement. Very annoying IMO. [image]
@daniel_mac8 Dan Mac on x
GPT-5.1 is a huge improvement in sycophancy. For example, it won't tell you that selling poop popsicles is a good idea. Believe it or not, GPT-4o would glaze you on any idea, including this one. (The full response made me genuinely LOL) [image]
@kimmonismus @kimmonismus on x
GPT-5.1 is LIVE! OpenAI just released GPT-5.1, a major upgrade making ChatGPT smarter, warmer, and more conversational. The new Instant model responds faster and adapts its reasoning for complex questions, while Thinking gives clearer, more human explanations with emotional [imag…
@kevinweil Kevin Weil on x
💥 Excited for GPT-5.1, rolling out starting today. It's the best combination of IQ and EQ we've ever shipped. It's smarter and warmer when you just need a quick answer, and calibrates its thinking time to the hardest questions—including scientific research. (GPT-5.1 Pro soon!)
@scaling01 @scaling01 on x
GPT-5.1 system card is a nothingburger as well https://cdn.openai.com/... [image]
@amanda.omg.lol Amanda Silberling on bluesky
literally the last thing chatgpt needs is to be “warmer” and “more conversational” (see: all of the lawsuits around the overly friendly/sycophantic gpt-4o's role in suicides/delusions) techcrunch.com/2025/11/07/s... [embedded post]
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