Regarding the claim that "GPT-5-1 Thinking has been officially confirmed by OpenAI," no corresponding name or announcement has been found on the OpenAI website, system cards, or developer documentation. OpenAI released GPT-5 in August 2025 and mentioned in several official materials that it could switch to or automatically route to the "gpt-5-thinking" model or mode, but there is no mention of "GPT-5-1 Thinking" or "gpt-5-1-thinking." What is confirmed is that GPT-5 is online, and there exists an official model/mode called gpt-5-thinking for deeper inference.
The term "GPT-5.1/5-1 Thinking" is frequently seen in third-party observations and social media posts, often citing the discovery of "gpt-5-1-thinking" in the ChatGPT frontend or source code traces as evidence. However, these sources lack official endorsement from OpenAI's website regarding the corresponding naming. Based on comparisons from multiple sources, the official existence of GPT-5 and gpt-5-thinking can currently be confirmed; models with the "5.1" designation remain rumors. If OpenAI releases official naming or version updates in the future, please refer to official blog posts, documentation, or system cards for confirmation.
Frequently Asked Questions
Q: Has OpenAI announced "GPT-5-1 Thinking"?
A: No official announcements or documents have been found that use this name; the only official mention is "gpt-5-thinking".
Q: What is GPT-5-thinking?
A: OpenAI's "Thinking" model/pattern, provided within the GPT-5 framework, is designed for more demanding inference tasks, as mentioned in official materials and help documentation.
Q: Is it credible that social media claims to have found "gpt-5-1-thinking" on the page/source code?
A: These kinds of clues are based on external observations and lack official documentation, so they cannot be equated with "official confirmation" at this time.
Q: Can I use the "Thinking" version now?
A: According to OpenAI's help and product page, ChatGPT will automatically or manually switch to GPT-5 Thinking; the availability and quota of options such as "Thinking/Pro" vary depending on the subscription tier, please refer to the official instructions.
Q: How to distinguish between authenticity and timelines?
A: Check if it appears in the release, system card, or development documentation on openai.com, and distinguish between the rumored release time and the event itself (e.g., GPT-5 was released in August 2025) to avoid mistaking external posts for official announcements.
