OpenAI DevDay 2026 (September 29) shipped the official product builders have been reverse-engineering all year: Sign in with ChatGPT. You can use your ChatGPT account on partner products, and — for Plus and Pro — spend included plan allowance inside those products instead of forcing every demo onto the developer's API key.
This is not a one-line login button with a hidden meter. OpenAI's recap names 16 launch partners, including Cognition's Devin, Notion, Vercel, T3, OpenClaw, and Dactyl. You can control how much each partner can use. Eligible OpenAI usage counts toward your existing plan limits. Identity sign-in is available globally. Plan usage is the narrower Plus/Pro lane.
OpenAI Codex and ChatGPT engineering lead Tibo Sottiaux put the consumer pitch in one post: you can now use your ChatGPT subscription directly in over 16 partner products. "No little rules, you can just use all your included usage right there." He named Devin, OpenCode, Notion, and more. "Sign in with ChatGPT and go."
This post is the builder read: what actually shipped, how it differs from the June unofficial OAuth experiment, why a16z's distribution thesis just got a concrete primitive, and the Notion workspace caveat people are already hitting.
TL;DR — what people are asking
| Question | Direct answer |
|---|---|
| What shipped? | Official Sign in with ChatGPT: identity + eligible Plus/Pro plan usage in partners |
| When? | Announced at DevDay 2026 on September 29; this recap is September 30 |
| How many partners? | 16 launch partners for plan usage; OpenAI says more will follow |
| Named in the official recap | Cognition's Devin, Notion, Vercel, T3, OpenClaw, Dactyl (plus others in press lists) |
| Who gets plan usage? | ChatGPT Plus and Pro in participating tools |
| Who gets identity? | Authenticated ChatGPT users globally, including many Enterprise seats subject to admin settings |
| Does usage stack on my plan? | Yes — eligible OpenAI usage counts toward plan limits |
| Can I cap a partner? | Yes — per-app controls in ChatGPT settings |
| Is this the June hack? | No — that was unofficial; this is the sanctioned product |
| Does Notion Plus-or-Pro-only work? | Unlikely — community notes say you also need Notion Business or Enterprise |
What actually shipped (two products, one button)
The confusing part of the announcement is that the same phrase now covers two capabilities.
Identity. You sign into a tool with your ChatGPT account — name, email, profile picture — the way you would with a Google or Apple button. OpenAI's help article describes this as creating, linking, or accessing an account on a supported site, including some ChatGPT plugins and partner web apps. That identity path is available globally. Extra plugin scopes still need a separate approval.
Plan usage. Eligible OpenAI usage inside a participating product counts toward your ChatGPT plan limits. That is the DevDay headline. It is Plus and Pro in participating tools, not a free-tier token dump. You decide how much each partner can burn.
Those two are not the same click. A product can offer ChatGPT login without touching your included Codex or Work allowance. A product can also consume eligible usage after you connect the plan. Check the partner's settings screen, not just the button label.
This is also not ChatGPT's cloud browser signing into someone else's website. That flow authenticates a remote browser to Gmail or a bank so an agent can finish a task. We already separated those directions in the signed-in websites post. Sign in with ChatGPT is the other way: the partner uses your ChatGPT identity (and sometimes your quota).
Who is in the 16, and what "eligible" means
OpenAI's official recap highlights 16 partners, including Cognition's Devin, Notion, Vercel, T3, OpenClaw, and Dactyl. Press recaps of the same keynote also list tools already in the Codex-adjacent ecosystem: OpenCode, Pi, Hyperagent, Hermes Agent, Vorflux, Amp, Kilo Code, Warp, Conductor, with Lovable described as coming soon. Treat the extra names as reporting, not a substitute for the in-product partner list in ChatGPT settings.
Eligible is the word that does the legal work. It means OpenAI-shaped inference the partner routes through the program — not compile minutes, image generation credits, storage, or a partner seat. Dactyl-style products have already shown the split in public: the agent that writes code can ride a ChatGPT subscription, while compile, icons, or publish steps still consume the partner's own credits. Expect that pattern everywhere.
When a cap or plan limit hits, included usage stops. It does not automatically flip onto the partner's card. That is friendlier than a surprise invoice and worse than "the agent keeps going." Design your loops as if the partner can go dark mid-task.
Plan details and current prices stay on chatgpt.com/pricing. Official identity help is on OpenAI's Sign in with ChatGPT article.
Notion: Plus or Pro is not the whole story
Notion's own message is the one users will screenshot: ChatGPT Plus or Pro can cover AI usage in Notion if you connect the plan and pick a GPT model.
Community notes on X add a hard filter. People report that this still requires a Notion Business or Enterprise workspace in addition to ChatGPT Plus or Pro. A personal Notion workspace plus a Plus seat is not enough.
That caveat is the most useful sentence in this post if you manage a team. Budget two SKUs, not one. Confirm in Notion's workspace admin and ChatGPT's connected-app list before you tell finance that "Plus covers Notion AI."
If the community note is wrong on your tenant, you will see the GPT model picker after connecting the plan. If it is right, you will see a workspace-plan wall. Do not argue from the marketing sentence; argue from the settings page.
Nous Portal and Hermes Agent
Nous Research said Sign in with ChatGPT is live on the Nous Portal for Hermes Agent. Visibility and controls sit in ChatGPT settings, not only in Nous's dashboard.
That is the control-plane story OpenAI wants: one place to see which partners can spend included usage, and one place to cut them off. If you already run Hermes as a daily agent, connect it, set a weekly cap, and watch the usage page for a week before you treat it as "free Codex everywhere."
The same settings surface is where you should audit Devin, OpenClaw, and any other agent that can loop without asking. Always-on partners plus uncapped included usage is how a Plus bar disappears on a Tuesday.
Official product vs June's reverse-engineered OAuth
In June, Savio Martin's LoginWithChatGPT wrapped Codex CLI device authorization into a web button so indie apps could run prompts on the user's ChatGPT quota. We covered the TOS risk, the demo model path, and the "should you ship this" answer in LoginWithChatGPT: Codex subscription OAuth. The honest status then: OpenAI had not shipped this, and production use was a bet.
This DevDay launch is the official product that June post was waiting for. Same economic idea — BYO quota, developer API bill toward zero — different legal and security posture. Official partners get a sanctioned token, usage accounting, and a revoke path in ChatGPT settings. Unofficial device-code wrappers still sit next to the sub2api pooling pattern Tibo already called unsupported.
| June LoginWithChatGPT | Official Sign in with ChatGPT | |
|---|---|---|
| Who shipped it? | Independent experiment | OpenAI, DevDay 2026 |
| Auth shape | Reverse-engineered Codex device auth | First-party partner program |
| Who pays eligible tokens? | User's ChatGPT plan | User's ChatGPT plan (Plus/Pro) |
| TOS posture | Unclear; wait-and-see | Supported for participating partners |
| Per-app caps in ChatGPT | No official settings UI | Yes |
| Should you build on it? | Demo only | Yes, if you are (or become) a partner |
If you still have a prototype on device codes, stop pointing production users at it. Point them at the partner button. If you are not a launch partner, the June post's advice still holds: do not collect ChatGPT credentials on shared infra and hope.
Who owns the customer — Peter Yang's question
Product lead Peter Yang called the move a game changer: Sign in with ChatGPT plus letting people use their ChatGPT plan inside your app. Then he asked the ownership question that actually matters: who owns the relationship — the app or OpenAI?
That is the same fight David George sketched the night before DevDay. Partnerships buy reach. Platforms buy the learning loop. Sign in with ChatGPT is both at once.
BYO-quota is the founder's gift. Your first-week inference COGS can go toward zero because Plus and Pro users arrive with tokens already paid. Altman said the quiet part on stage: people are already paying for an AI subscription, so you do not have to cover their token costs just to get them to try the product. That is a real CAC change for agent products that used to bleed API invoices on every trial.
Login gravity is OpenAI's gift to itself. The user signed in with ChatGPT. Usage shows up in ChatGPT settings. Revoke lives in ChatGPT settings. When the partner ships a worse model picker or a higher seat price, the user still has an OpenAI account and a habit of spending quota through OpenAI's pipe. The app can own the workflow. OpenAI owns the wallet and the identity.
Builder translation:
- If you are a partner, treat included usage as trial fuel, not a forever subsidy. Your paid SKU still has to be something ChatGPT cannot revoke in one settings toggle — data, workflow, team permissions, compile, deploy.
- If you are not a partner, you are now competing with products whose demos are "free" to Plus users. Price on outcomes, not on "we eat the tokens."
- If you are a buyer, assume two bills: ChatGPT Plus or Pro, plus the partner seat. Notion's Business/Enterprise wall is the prototype of that stack.
What this means for what you build or pay
Consumers and prosumers. Connect one partner. Set a cap. Watch chatgpt.com/pricing and the usage page for a week. Do not connect Devin, OpenClaw, Hermes, and Notion on day one with uncapped spend. Eligible usage is still your bar.
Indie builders. The June dream is now a partner program, not a component you npm-install. Apply or wait. Meanwhile, keep a real API path so users without Plus can still pay you.
Platform teams. Decide whether ChatGPT identity is allowed in your SSO policy. Global availability does not override your IdP. If contractors sign into Devin with personal Plus seats, you just created a shadow AI spend line that never hits the company OpenAI invoice.
OpenClaw / Codex-harness users. You already had subscription-backed Codex auth in some clients. Official Sign in with ChatGPT is the version with ChatGPT-side tracking. Prefer it over pooled proxies. The August sub2api writeup is still the fraud-flag map: shared subscription-to-API relays get treated as abuse; signing in as yourself does not.
What people are asking
Does this make my ChatGPT Plus "unlimited" across the internet?
No. Eligible usage still decrements the same plan limits. Sixteen partners sharing one Plus bar is how you hit the wall faster, not slower. Per-app caps exist because OpenAI expects that failure mode.
What about ChatGPT Free, Go, Business, or Enterprise?
Identity can apply more broadly than plan usage. Plan usage in the DevDay recap is Plus and Pro in participating tools. Enterprise identity may be on while plan sharing is off, or gated by an admin. Do not promise finance that every ChatGPT SKU portable-izes tokens.
Is this safer than pasting an API key into a random site?
Usually yes, if you stay on official partners and revoke in ChatGPT settings. You are still authorizing a third party to spend your quota and to receive identity fields. Read the partner's data policy. Eligible usage does not mean the partner cannot store prompts.
Will partners stop charging?
Unlikely. They will charge for the part that is not eligible OpenAI usage: seats, storage, evals, deploy, support. Some will advertise "runs on your ChatGPT subscription" the way Dactyl already did. Read the asterisk.
Should I rip out BYOK?
Keep BYOK or a metered API path for users who are not Plus/Pro, for regions or workspaces that block the program, and for when a cap hits mid-job. Official Sign in with ChatGPT is a second wallet, not a replacement architecture.
A checkout list you can run today
- Open ChatGPT settings and find connected apps / Sign in with ChatGPT controls.
- Connect one partner you already pay for. Skip the full 16.
- Set a weekly cap below your comfort level. Confirm the unit (requests vs tokens) in the UI — OpenAI's recap says you control how much each app can use; the exact widget may still be rolling out.
- Run a known task (one Notion AI rewrite, one Devin ticket, one OpenClaw turn). Screenshot usage before and after.
- If you use Notion, verify workspace plan (Business or Enterprise) before you tell the team Plus is enough.
- If you use Hermes on Nous Portal, confirm the same spend appears in ChatGPT settings, not only on Nous.
- If you still have a June-style device-code prototype, disable it for anyone but yourself.
Honest limitations
- Partner list will move. Sixteen is a launch number. Do not hard-code it into a procurement deck.
- Eligible is undefined in public docs at the token-type level. Until OpenAI publishes a developer table (which models, which endpoints, Work vs Codex buckets), assume conservative coverage.
- No official video ID was provided for this recap, so we are not embedding a guessed clip. Watch OpenAI's own DevDay stream if you want the keynote wording.
- Admin and region gates still apply. Global identity is not the same as every workspace enabling plan sharing.
- Dots and plugin extensions from the same keynote are a separate distribution story. See the DevDay announcements recap for that stack.
The bottom line
Sign in with ChatGPT is OpenAI turning a year of unofficial "use my sub" hacks into a first-party wallet. Plus and Pro users can spend included usage in 16 partner products, cap each one, and sign into tools and plugins with the same account. Identity is global. Plan usage is not.
For users, that is real convenience and a faster way to empty a Plus bar. For founders, it is cheaper trials and a sharper question: when the quota lives in ChatGPT settings, who does the customer think they bought?
Related reading
- OpenAI DevDay 2026: every announcement
- LoginWithChatGPT unofficial Codex OAuth (June)
- Codex limits vs sub2api — Sign in With ChatGPT
- a16z's David George on OpenAI distribution
- ChatGPT Voice, plugins, and Work
- Cloud browser vs Sign in with ChatGPT
- OpenClaw on ChatGPT Plus / Pro subscriptions
- Official: Sign in with ChatGPT help · ChatGPT pricing · OpenAI
Partner lists, eligibility, and per-app controls reflect OpenAI's DevDay 2026 recap, OpenAI help text, and public posts as of September 30, 2026. Confirm live ChatGPT settings and partner admin screens before you change billing or procurement.