On December 6, according to NeowinOpenAI Yesterday, it officially launched its most powerful everProgramming Model GPT – 5.1 – Codex – Max, open to API use at “unexpectedly low prices”。
the new model, designed for long-duration intelligent programming missions, is able to work continuously in a context window of more than one million tokens, and internal tests show that it can perform more than 24 hours of continuous operations。
GPT – 5.1 – Codex – Max performed better than the conventional version in a number of benchmark tests: 779% on SWE – Bench Verified, 79.9% on SWE – Lancer IC SWE and 581% on Terminal Bench 2.0。
In contrast, regular GPT ‐5.1 -Codex performed 73.7%, 66.3% and 52.8% respectively. OpenAI indicates that the model will not only be faster and token will be more efficient, but will also be the Codex default model。
In terms of pricing, GPT – 5.1 – Codex – Max is consistent with GPT – 5, input token $1.25 per million, output token $10 per million。
Previously, the model was limited to such channels as Codex CLI, IDE Extension, Cloud and Code Review, and was open to ChatGPT Plus, Pro, Business, Edu and Enterprise users。
Today, through API, developers can call the model directly in tools such as Cursor, GitHub Copilot and Linear。
It is worth noting that GPT5.1-Codex-Max optimizes the Windows environment, which is different from the Codex model, which was previously mainly oriented towards the Unix system. OpenAI is seen as a strategic move to further expand the group of developers。
On the competition level, OpenAI's main opponent Anthropic Claude Code has rapidly emerged as the fastest growing SaaS product and is expected to receive between $8 billion and $10 billion this year。
Since August, when GPT –5-Codex was released, the use of the OpenAI Codex model has increased more than 10 times, with the number of tokens processed weekly reaching trillions. The industry is concerned about whether the new model will be effective in curbing the strong momentum of Anthropic in the enterprise-level programming market。