1# October 5–9, 2026

2 

3> For the complete documentation index, see [llms.txt](https://learn.chatgpt.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to the page URL.

4 

5[Back to What's new](https://learn.chatgpt.com/docs/whats-new#october-59-2026)

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7## Use GPT-6.1 Sol with Ultrafast mode

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9Ultrafast mode speeds up token generation with [GPT-6.1 Sol](https://learn.chatgpt.com/docs/models#gpt-61-sol)

10in Codex and ChatGPT Work. Ultrafast is available on Pro $500 and eligible

11Enterprise and Edu plans.

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13Enterprise access is off by default; workspace owners must enable it.

14GPT-6.1 Sol Ultrafast supports inference residency in the United States and

15Europe (EEA + Switzerland).

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17See [Ultrafast mode](https://learn.chatgpt.com/docs/agent-configuration/speed#ultrafast-mode) for plan

18and workspace requirements and [Pricing](https://learn.chatgpt.com/docs/pricing) for usage and credit

19rates. Read the [launch announcement](https://learn.chatgpt.com/docs/changelog#codex-2026-10-08-gpt-61-sol-ultrafast).