GPT-5.1
Launch date: November 12, 2025
OpenAI today announces the release of GPT-5.1, a major update to the GPT-5 series, aimed at making the ChatGPT experience smoother, more customizable and better aligned with the expectations of French-speaking and international users.
GPT-5.1 Instant
The version Instant is positioned as the default model, used in the majority of interactions:
Ton warmer by defaulta conversation that "feels less robotic".
Improved ability to follow your instructions : the AI remains more faithful to the brief than in previous versions.
New “adaptive reasoning”: the model automatically decides whether to “think longer” to answer or to respond immediately depending on the complexity of the task.
Improved results on coding or math tasks: OpenAI cites measurable performance on the AIME 2025 and Codeforces assessments.
GPT-5.1 Thinking
The version Thinking is dedicated to more complex tasks, in-depth reasoning or work content:
For simple tasks, Thinking is twice as fast than the previous GPT-5 version. On long or complex tasks, it may take up to twice as long to provide a more complete answer.
The model uses less jargon, offers clearer explanations, and is better suited to French-speaking professional users.
Ideal for document analysis, technical writing, or assisting with demanding workflows.
Further customization
OpenAI adds to both variants the ability to customize the AI's response style:
Many tone and personality presets : Professional, Friendly, Efficient, Quirky, Nerdy, Cynical…
The settings take effect immediately, even in the middle of an ongoing conversationallowing the user to change the atmosphere of the dialogue in real time.
For a French audience, these settings allow you to adjust the language, register and wording according to the cultural target: professional email, blog, casual conversation, etc.
Deployment and accessibility
The launch begins with paid subscribers (Plus, Pro, Business) and will soon extend to free users.
The older GPT-5 versions will remain temporarily available in a "legacy" menu for comparison.
API access is planned for both Instant and Thinking variants in the coming days.
Comparison of GPT-5 vs GPT-5.1 models
| Criterion | GPT-5 | GPT-5.1 |
|---|---|---|
| Release date | August 2025 | November 2025 |
| Proposed versions | “Standard” model + “thinking”/reasoning versions | Two variations: Instant et Thinking |
| Conversational style/tone | A significant improvement compared to previous versions, but still perceived as “less welcoming”. | Your tone will be warmer, conversation more natural, style personalized |
| Follow the instructions | Very good, but some user feedback notes discrepancies in the exact execution of the prompt. | Improved instruction tracking: AI remains more faithful to user instructions |
| Adaptive reasoning / complexity management | “Multi-model” architecture: fast or deep depending on the task | Introduction of "adaptive reasoning": "Instant" for simple tasks, "Thinking" for complex tasks |
| Customizing tone and style | Limited options for adjusting tone/personality | Many more personality presets (Friendly, Professional, etc.) and finer style control |
| Performance & benchmarks | Very high performance (mathematics, coding, multimodality) for its time | Targeted performance improvements + better interactions, better fit for the French context |
| Availability & Deployment | Quickly becomes the default model after launch | Gradual rollout: first to paying subscribers, then general access; previous version available as a legacy service for a few months. |
Why does this matter to the French-speaking user?
The Instant version improves the "conversational" experience in French, reducing awkward or overly literal phrasing.
The Thinking version allows French-speaking users to use AI in professional tasks (writing, analysis, coding) with a rendering more suited to the expectations of French companies.
Personalizing the tone proves particularly useful for the French market, where register and politeness differ greatly depending on the context (admin, B2B, start-up, research).
The fact that GPT-5.1 takes into account the complexity of the task (via adaptive reasoning) translates into a smoother experience for users at different levels: student, professional, content creator.
Note a few points of vigilance
Although real progress has been made, some internal assessments show that GPT-5.1 presents some regressions on sensitive categories (violent content, sexuality, hate speech) compared to GPT-5.
It remains essential to check the AI results, especially for professional or technical content: generative models are not infallible.
For French users, compliance with the GDPR and privacy remains an imperative, especially in a multilingual and professional context.
In short
GPT-5.1 is more than just an update This represents a transition towards a better-behaved, more customizable, and more genuinely useful AI for a wide range of users. For French-speaking audiences, these improvements mean a more natural AI, better adapted to local needs, whether for writing, analysis, or conversation.
If you already use ChatGPT, this update is well worth testing both variants (Instant and Thinking) and exploring the new tone settings to see the difference.