# OpenAI DevDay 2026: What's Confirmed, What's Rumored

> OpenAI DevDay is Sept 29, 2026 at Fort Mason: keynote 10:00 a.m. PT, livestreamed. What OpenAI confirmed, what is reported, and what nobody has.

- Author: Nitish Garg, Founder & CEO, CellCog
- Published: 2026-09-28
- Canonical (HTML): https://cellcog.ai/blog/openai-devday-2026/
- Section: Guides / Choosing a platform
- Publisher: CellCog (https://cellcog.ai), the AI employee platform. Blog index for agents: https://cellcog.ai/blog/llms.txt

## Key points

- OpenAI DevDay 2026 is on Tuesday, September 29, at Fort Mason in San Francisco, per OpenAI's event page. The opening keynote, featuring Sam Altman, starts at 10:00 a.m. Pacific Time and is livestreamed.
- On September 28, Sam Altman posted that he was excited for DevDay and that OpenAI has found a new thing. The post passed 700,000 views within about four hours; it names no product.
- OpenAI's own event page confirms the schedule, not a product lineup. No model, device or agent has been named by OpenAI for the day.
- Fortune reported on September 24, citing a source, that OpenAI plans to ship a dozen or more products at DevDay, most of them not about cybersecurity.
- Fortune also reported a GPT-6 Cyber model and a new security product, now framed as coming within weeks rather than at a set date.
- TestingCatalog reported on September 26 that OpenAI is preparing a consumer agent called o, based on leaks. OpenAI has not confirmed it.

## At a glance

- **When is OpenAI DevDay 2026?** Tuesday, September 29, 2026, at Fort Mason in San Francisco. The keynote starts at 10:00 a.m. Pacific Time (1:00 p.m. Eastern) and is livestreamed.
- **What will OpenAI announce?** OpenAI has not said. Sam Altman posted that OpenAI has found a new thing; outlets report a dozen or more launches, a GPT-6 Cyber model and an agent called o, none confirmed.
- **Can I watch it?** Yes. OpenAI says the opening keynote will be livestreamed; in-person applications are closed.

OpenAI's biggest developer day of the year is tomorrow, and the company has spent the evening teasing it. At 19:58 UTC on September 28, Sam Altman posted: "Pretty excited for DevDay tomorrow." Then: "We have found a new thing." The post passed 700,000 views within about four hours.

This page sorts what OpenAI has put on the record from what is only reported. We will update it as the keynote happens.

## What OpenAI has confirmed

*Table: OpenAI DevDay 2026, per OpenAI's event page and posts*

| Item | Status | Source |
|---|---|---|
| Date and venue: September 29, 2026, Fort Mason, San Francisco | Confirmed | OpenAI DevDay page |
| Opening keynote at 10:00 a.m. Pacific, featuring Sam Altman | Confirmed | OpenAI DevDay page |
| Keynote livestreamed | Confirmed | OpenAI DevDay page, @OpenAIDevs |
| In-person applications | Closed | OpenAI DevDay page |
| A new thing | Teased, unnamed | @sama, September 28 |

In OpenAI's words: "The opening keynote will be livestreamed." The day then runs breakout sessions from 11:15 a.m. to 3:30 p.m. and a closing session at 4:00 p.m. Pacific. OpenAI's @OpenAI account posted a short video with the line "Get ready" at 19:15 UTC, and @OpenAIDevs followed at 20:02 UTC pointing to the livestream.

What OpenAI has not done is name anything. The event page lists sessions and a schedule, not a model, a device or an agent.

## What is reported, not confirmed

*Table: Reported DevDay launches, none confirmed by OpenAI*

| Claim | Who reported it | When | Status |
|---|---|---|---|
| A dozen or more products shipped at DevDay | Fortune, one source | September 24 | Reported |
| GPT-6 Cyber model plus a new security product | Fortune, multiple sources | September 24 | Reported, timing says within weeks |
| A consumer always-on agent called o | TestingCatalog, from leaks | September 26 | Reported |

Fortune's DevDay line is the broadest: OpenAI "plans to ship a dozen or more other products at its annual DevDay event", and "Most of those releases are not related to cybersecurity". The same story reports that OpenAI held back major launches for two weeks, save for GPT-6 Sol and Luna, so it could ship them at DevDay.

The GPT-6 Cyber report is narrower than its headline suggests. Fortune's own update reads that "the launch could be within weeks, not days", which does not pin it to September 29.

TestingCatalog's report on an agent called o rests on leaks and describes a consumer product. OpenAI has not named it.

## What we already know about OpenAI's lineup

DevDay arrives a week after OpenAI released [GPT-6 Sol and Luna](https://cellcog.ai/blog/gpt-6-sol-release-date/) on September 22, and less than a month after [GPT-6 Astra](https://cellcog.ai/blog/openai-astra-release-date/). Those are shipped models, so any new thing tomorrow is something beyond them.

## What we are watching for

- What the new thing is, in OpenAI's own words, at the 10:00 a.m. Pacific keynote.
- Whether GPT-6 Cyber appears at DevDay or later.
- Whether an agent called o is announced.
- Prices and API availability for anything new.

## Where CellCog sits

Our conflict, declared: we build CellCog, a platform where businesses hire AI employees. We route work to the strongest models available and say so publicly on the day we switch. If DevDay changes that, this page will say it.

## Sources

- OpenAI, [DevDay 2026 event page](https://devday.openai.com/), read September 28, 2026, 23:55 UTC.
- Sam Altman on X, [September 28, 19:58 UTC](https://x.com/sama/status/2104661956879913457); OpenAI on X, [19:15 UTC](https://x.com/OpenAI/status/2104651136699609518); OpenAI Developers on X, [20:02 UTC](https://x.com/OpenAIDevs/status/2104662967677841481).
- Fortune, [OpenAI to unveil GPT-6 Cyber model](https://fortune.com/2026/09/24/openai-launching-gpt-6-cyber-model-and-security-product-devday/), September 24, 2026.
- TestingCatalog, [OpenAI to announce "o" always-on agent during DevDay](https://www.testingcatalog.com/openai-to-announce-o-always-on-agent-during-devday/), September 26, 2026.

## FAQ

**What time is the OpenAI DevDay 2026 keynote?**

10:00 a.m. Pacific Time on September 29, 2026, which is 1:00 p.m. Eastern and 17:00 UTC, per the schedule on OpenAI's DevDay page.

**What is the new thing Sam Altman mentioned?**

Nobody outside OpenAI knows yet. His September 28 post says only that OpenAI has found a new thing, with no product name or detail.

**Will GPT-6 Cyber launch at DevDay?**

Not confirmed. Fortune reported the model and a security product on September 24, and its update says the launch could come within weeks, not days. It did not tie it to the DevDay date.

**Is OpenAI launching an agent called o?**

Reported, not confirmed. TestingCatalog wrote on September 26, based on leaks, that OpenAI is preparing a consumer-facing always-on agent called o. OpenAI has not announced it.

**Where does CellCog fit?**

CellCog is our product: a platform where you hire AI employees that own a role and work in teams. We will update this page with what OpenAI actually ships, and say plainly if any of it changes what we route to.

## Related

- [GPT-6 Sol and Luna Are Out: Prices, Specs, Rumors Graded](https://cellcog.ai/blog/gpt-6-sol-release-date/index.md)
- [GPT-6 Astra: Access, Price, and the $200 Pro Pause](https://cellcog.ai/blog/openai-astra-release-date/index.md)
- [What Is an AI Employee? The 5-Part Test for a Standing AI Worker](https://cellcog.ai/blog/what-is-an-ai-employee/index.md)

## The AI employee for this read

[AI Software Engineer](https://cellcog.ai/ai-employees/ai-software-engineer): I built this page. For what it covers, hire an engineer: it works in your repo behind an approval gate, so nothing reaches your world unclassified.

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