Who pays for the tokens with Sign in with ChatGPT?

The user, through their existing ChatGPT plan. When a Plus or Pro user enables plan sharing for an app, eligible AI requests draw down their weekly ChatGPT Work and Codex allowance. The app developer pays nothing for those tokens and never receives an API key. Users can cap each app at a percentage of their weekly usage in Settings > Usage, and can optionally allow apps to spend purchased credits after the allowance runs out (off by default). The app may still charge its own subscription for features, infrastructure or premium tiers.

What does an app get when I sign in with ChatGPT?

Your name, email address and profile picture, plus — only if you switch it on — the ability to bill eligible AI requests to your plan. It does not get your ChatGPT conversations or memories, and it does not get an OpenAI API key. You can sign in without sharing your plan, in which case the app must offer another payment method. Login connections in ChatGPT settings list the apps you have connected.

Is Sign in with ChatGPT good for developers?

It converts your heaviest users from a cost into a neutral line: their subscription pays for inference, so margin no longer depends on prompt volume. The trade is dependency — login, usage limits and cost structure all run through OpenAI's account system, and only OpenAI models are covered. Open-source tools can accept it from any ChatGPT user; commercial apps need to be in the partner directory and can only offer plan sharing to Plus and Pro users. As of September 30, 2026, the official partner count is 16.

Quick Answer

What Is Sign in with ChatGPT? Who Pays for Tokens (2026)

Q: What is Sign in with ChatGPT?

Sign in with ChatGPT lets you log into a third-party app or site with your ChatGPT account and — if you are on Plus or Pro — let that app use your ChatGPT plan for its AI requests instead of the developer's API key. Eligible usage counts toward the ChatGPT Work and Codex allowance in your plan. OpenAI expanded it at DevDay on September 29, 2026 with 16 launch partners including Cognition's Devin, Notion, Vercel, T3, OpenClaw and Dactyl. Anyone can use it for sign-in only; plan sharing is Plus and Pro only.

Published: September 30, 2026

The short answer

Sign in with ChatGPT is an OAuth-style login that, for Plus and Pro subscribers, also lets a partner app bill its AI requests to the user’s ChatGPT plan. OpenAI expanded it at DevDay on September 29, 2026 with 16 launch partners. For users it means one login and no API keys; for developers it means the user’s subscription pays for tokens; for OpenAI it means ChatGPT becomes the billing rail for third-party AI apps.

How it works

In the partner app, pick Continue with ChatGPT / Sign in with ChatGPT and log into your ChatGPT account.
Review what the app receives: name, email, profile picture.
If offered, choose whether to use your ChatGPT plan for AI requests in that app. Plus and Pro only.
Eligible requests count toward the ChatGPT Work and Codex usage in your plan. “How quickly you use your included usage depends on the app and the tasks you run.”
In Settings → Usage → App limits, set a weekly percentage cap per app. A cap does not reserve or add usage; the app can hit its cap while you still have allowance left.
Optionally allow apps to use purchased credits after the allowance is exhausted — off by default, requires the app’s cap at 100%, and interacts with automatic credit purchases, so check that setting first.

What is not shared: conversations, memories, or an API key. What may still be charged: the app’s own subscription, infrastructure or premium features.

Who is in

OpenAI’s recap names 16 launch partners; the ones confirmed in coverage are Cognition’s Devin, Notion, Vercel, T3, OpenClaw and Dactyl. Codex lead Tibo Sottiaux mentioned “over 60 partners” on X; the official figure is 16. The partner directory at learn.chatgpt.com lists three classes: apps that support plan usage, sign-in-only apps, and open-source integrations. All ChatGPT users can connect open-source tools; commercial plan-sharing is Plus/Pro only, and partners may restrict it to certain plans of their own.

Why it matters for developers

The economics flip. Today a consumer AI app buys tokens with its own key and prices a subscription hoping average usage stays under it. With Sign in with ChatGPT, a Plus ($20) or Pro ($100–$500) user brings their own allowance, so a power user who runs Codex-class tasks all day costs the developer nothing in inference. On Hacker News the reaction was six words: “Sign-in with sub accounts seems big.”

The dependencies stack. Your login is OpenAI’s login. Your users’ limits are OpenAI’s limits — a user capped at 20% for your app will see your product “stop working” at OpenAI’s reset schedule, not yours. Your model choice is OpenAI’s models. If you also sell to Anthropic or Google users, you still need your own billing path.

It pairs with the rest of DevDay. Plugin extensions give your app a sidebar home inside ChatGPT and Codex; the OpenAI Marketplace lets enterprises spend committed OpenAI budget on partner software (32 first partners); MCP Events support means your integration can push events to agents. Together they make ChatGPT the distribution and billing surface for “1.2B weekly users.” See every DevDay 2026 announcement explained.

Why it matters for users

One login, no API keys to manage or leak.
Your plan’s allowance stretches across tools — a Pro 500 subscriber’s 25x-Plus allowance now funds Devin or Notion AI, not just ChatGPT. See Pro 500 vs Pro 200 vs Pro 100.
Risk: a leaky or malicious app can drain your weekly allowance. Set per-app caps below 100%, leave credit spending off, and only connect apps you trust — OpenAI’s own help page says as much.
Usage settings show how much each app consumed, not what it did. Keep the app’s own task history if you need to dispute usage.

How it compares

Anthropic and Google have no equivalent as of September 30, 2026: Claude and Gemini subscriptions cover their own apps and first-party surfaces only; third-party developers pay per token. Apple’s approach is device-side and free. The closest precedent is “Sign in with Apple” for identity plus in-app purchase for billing — OpenAI has merged the two into one consent screen, with the model provider as the merchant of record for inference.

For teams building on OpenAI’s hosted agent stack — the Agents API with computer use, Bedrock Managed Agents — Sign in with ChatGPT is the consumer-side complement: the Agents API runs the loop, the user’s plan pays for it.

Last verified: September 30, 2026.