By Si Fisher · Published
That “Continue with ChatGPT” button can be a name badge—or permission to dip into your AI allowance. Those are two very different clicks. In participating apps, you can sign in with the account you already use. If you have Plus or Pro, some apps can also use the AI usage included in your plan, but only if you separately allow it. Signing in alone does not open your old ChatGPT conversations to the app.
Before you click through, make three decisions: am I comfortable sharing my basic account identity; do I want this app to use part of my shared ChatGPT Work and Codex allowance; and does the app ask for any additional access to data or actions? Its own subscription can still cost money. Three decisions, one button trying to look innocent.
Try an eligible app faster
Use your ChatGPT account and, when offered, your existing Plus or Pro usage without setting up an API key.
Allow plan use separately
Signing in does not automatically let the app use your included AI allowance.
Cap use; read app fees
A per-app cap limits its share of your allowance. It does not pay the app’s separate bill.
What does Sign in with ChatGPT actually buy you?
Convenience first. At a participating app or site, you can choose “Continue with ChatGPT” instead of creating another login. If that app supports plan usage and your ChatGPT account is eligible, you can separately let eligible AI requests use your Plus or Pro allowance. You do not hand the app an OpenAI API key. That makes it worth considering for a tool you already wanted to try—not a reason to install every app that grows a shiny new sign-in button.
OpenAI distinguishes sign-in-only partners from those offering plan usage. A free ChatGPT user may be able to sign in but cannot share a Plus or Pro allowance they do not have. A participating app may reserve its plan-sharing option for certain tiers of its own service. Check the prompt you actually see and the app’s current terms rather than assuming every integration works alike.
What can the other app see?
Think of three separate keys:
- Sign-in identity: the external app receives your name, email address and profile picture if you have one.
- Optional plan usage: when offered and approved, eligible AI requests count against your shared Work and Codex usage.
- Other delegated access: any app-specific request to use data or take actions needs its own review.
OpenAI says signing in or sharing the plan alone does not give the partner your ChatGPT conversations, memory, files, billing details or an API key. A partner may request more access separately, so read that permission screen too. OpenAI explains the identity boundary here.
That boundary goes both ways: a partner can still collect what you type inside that partner’s own product under its policies. “It cannot see my old ChatGPT chats” is not the same as “nothing I do in the app is recorded.” For a client document or sensitive workflow, read the partner’s privacy terms before using the connection.
Will it use my allowance or cost more?
If you approve plan sharing, eligible AI requests in the partner app draw from the ChatGPT Work and Codex usage included in your Plus or Pro plan. In ChatGPT Settings → Usage, OpenAI says you can inspect usage by app and set its weekly limit as a percentage of your overall weekly usage. A 25% app cap is a ceiling on that app’s share, not a fresh 25% bonus pool. The app could hit its cap while you still have overall usage left. Different tasks or apps may consume usage at different rates. Check the current usage guide for your account.
The partner may charge its own subscription, infrastructure or premium-feature fees on top. Your ChatGPT plan does not automatically pay those charges. Look at the app’s pricing before treating “use your plan” as “free app.”
Credits add one more choice if the included allowance runs out. OpenAI says partner-app credit use is off by default and may not be available to every account. For it to work:
- You must turn on the credit-use preference, which applies across participating apps.
- That app’s weekly limit must be set to 100%. Each app’s cap still applies; 100% by itself does not turn on credits.
- Your account must be eligible and have available credits.
Automatic credit purchases are a separate setting. If they are enabled, continued usage could bring charges without another notice at the moment included usage runs out. I would check both controls before starting a long job.
A sensible first connection—and how to undo it
- Start from the app you already intend to use. Confirm it actually offers Sign in with ChatGPT and, if you want it, the separate plan-usage option.
- Read the identity details and each additional permission. Approve only what the task needs; check the app’s own price and data policy.
- In ChatGPT Settings → Usage, choose a weekly app cap you are comfortable with and confirm the saved setting. Review credit sharing and automatic purchases separately.
- After a small real task, inspect the usage shown for that app. If something seems wrong, keep the task details; OpenAI’s usage view may not show a complete action-by-action history.
To stop the connection, go to ChatGPT Settings → Security and login → Login connections → Sign in with ChatGPT and disconnect the app. Merely signing out of the app does not revoke its ChatGPT connection. Disconnecting stops future authorization through that connection, but it does not erase usage already recorded or information the partner already received. You may also need the partner’s own deletion controls. These steps follow OpenAI’s current help.
If the app says you are ineligible, check which ChatGPT account is active, whether you have Plus or Pro, and whether that partner and its own plan support usage sharing. If it says you hit a limit, check both your overall allowance and the app cap before buying credits. Repeated sign-ins do not refill usage. For help choosing a subscription for a heavier workload, see my Pro 200 versus Pro 500 guide.
Quick questions
Does Sign in with ChatGPT let an app read my conversations?
No. OpenAI says identity sign-in and optional plan sharing do not by themselves give a partner access to your ChatGPT conversations or memory. Review any separate data or action permission the app requests.
Does a partner app get its own ChatGPT usage allowance?
No. Eligible requests use your included ChatGPT Work and Codex allowance. A weekly app percentage limit caps how much of that shared allowance the app can consume; it does not add usage.
Will setting an app limit to 100% charge my credits?
No. That limit alone does not enable credits. If available, credit use after included usage runs out needs a separate opt-in and a credit balance; automatic credit purchases are a separate setting to review.
Sources and method
I checked OpenAI’s Help Center and current integration documentation on September 30, 2026. This guide is based on documentation, not a hands-on test of partner apps. Availability and partner fees can change, so verify the prompts and terms in the app you choose. Corrections: hello@theprotoolkit.com.
- OpenAI, Using your ChatGPT plan in other apps and sites (Help Center, checked September 30, 2026)
- OpenAI, Sign in with ChatGPT (Help Center, checked September 30, 2026)
- OpenAI, Sign in with ChatGPT documentation (checked September 30, 2026)
Update log: September 30, 2026 — initial cross-app permission and usage guide. Recheck when OpenAI changes plan sharing, credit controls or partner eligibility.