At DevDay 2026, OpenAI announced GPT-6 Astra Ultrafast, Codex across devices and ChatGPT plan use in partner tools

Archive entry: this covers an event from September 29, 2026, and we published it on November 8, 2026. The details come from sources dated at the time and may have changed since.

On September 29, 2026, OpenAI published its DevDay 2026 recap, which counted more than 20 major announcements and cited 1.2 billion weekly ChatGPT users.

Models, API and Codex

• Ultrafast: up to 8x faster token generation (300 tokens per second) in Codex and up to 6x in the API. GPT-6 Astra Ultrafast was available in the API and in Work and Codex on Pro 500 and Enterprise, at $60 input and $300 output per 1M tokens, with global processing and US data residency only (EU not supported).
• Agents API: gained computer use, multi-agent support, tool search and compaction, and was available through the API and in Codex and ChatGPT Work on Pro 500 and Enterprise.
• Codex everywhere: developers could run Codex on a computer, remotely from a phone, or in the cloud from any device, with reusable development environments, and Codex CLI gained voice and an /agents view.
• Review and security: a code review experience in the ChatGPT desktop app covered GitHub pull requests and GitLab merge requests, with automatic reviews, on all plans. Codex Security Cloud was available on Pro, Business, Enterprise and Edu.

Plugins, partners and ChatGPT

• Plugin extensions: sidebar, interactive panels and file viewers arrived on all plans, with a Plugin Creator, a submission flow, plugins in Sites and support for the proposed MCP Events specification for plugin automations.
• Partner tools: ChatGPT plan allowances could be used across 16 partners, including Cognition's Devin, Notion, Vercel, T3, OpenClaw and Dactyl. Identity was available globally, plan usage was available to Plus and Pro users in participating tools, and Enterprise customers could apply OpenAI commitments to 32 partners.
• ChatGPT features: ChatGPT gained Space, Pages, Slides, Teams, @ChatGPT in Slack and Teams, a Meetings plugin and shareable profiles.

What it meant for builders

Partner tools could draw on ChatGPT plan allowances, and OpenAI pushed Codex further into code review and security, two areas where it competed with established developer tools.

Sources

• DevDay 2026 Recap (OpenAI, September 29, 2026, official)
• OpenAI News RSS feed (item: DevDay 2026 Recap) (OpenAI, September 29, 2026, official)
• OpenAI API changelog: Ultrafast for GPT-6 Astra; computer use in the Agents API (OpenAI, September 29, 2026, official)
• DevDay 2026 Recap (archived copy) (Internet Archive (Wayback snapshot of openai.com), September 29, 2026)
• ChatGPT & Codex changelog: GPT-6.1 Sol Ultrafast in Codex and ChatGPT Work (OpenAI, October 8, 2026, official)
• API credits for ChatGPT subscribers (OpenAI, official)

Written with AI assistance, strictly from the sources listed above. Before it went live, automated checks verified its dates, sources and every language edition.