For ChatGPT · Claude · Gemini · Perplexity · Copilot · Mistral · Poe · DeepSeek

Catch a leaked API key before it ever leaves your browser.

PasteSentinel is a browser extension that watches what you paste into ChatGPT, Claude, Gemini and other AI chat tools, and warns you the instant it looks like an API key, token or password. Cancel it, or send it anyway - your call, every time.

Coming soon to the Chrome Web Store See how it works

No account needed · Free · Runs entirely on your device, nothing is ever sent anywhere

Built to catch what you'd miss scanning by eye

A config file, a terminal log, a .env snippet - it's easy to paste the whole thing without noticing the key sitting inside it.

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Scans the instant you paste

PasteSentinel checks your paste before it lands in the chat box, not after you've already hit send.

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Recognizes real formats

AWS, GitHub, Slack, Stripe, OpenAI-style, Anthropic, Google, Twilio, SendGrid, npm, GitLab, Discord and dozens more - not just a generic "looks random" guess.

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Catches key files too

RSA, EC, OpenSSH, DSA and PKCS#8 (.p8) private keys, encrypted PEM blocks and PGP private keys. Your SSH .pub file is left alone - that one's meant to be shared.

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Also flags the unlabeled ones

No recognizable prefix, still looks like a real secret or a strong password? A local entropy check catches those too, without ever needing to know what your secrets look like.

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Teach it your exceptions

Using a placeholder or test key on purpose? Add it to your ignore list once, and PasteSentinel stops flagging it.

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100% local, always

No servers, no account, no analytics. The text you paste is scanned in memory and discarded immediately, even the secret itself if one is found.

Nothing to set up, nothing to remember

It works the moment it's installed, right inside the chat box you already use.

Paste like you always do

Drop a config file, a terminal log, or a .env snippet into ChatGPT, Claude, Gemini or another supported AI chat box.

PasteSentinel checks it instantly

Entirely on your device, in the moment you paste. Nothing is sent anywhere, even if it finds a secret.

You decide

Cancel the paste, or send it anyway. PasteSentinel never blocks anything silently without asking first.

Frequently asked questions

Which AI chat sites does PasteSentinel work with?

ChatGPT (chatgpt.com, chat.openai.com), Claude (claude.ai), Gemini (gemini.google.com), Perplexity (perplexity.ai), Microsoft Copilot (copilot.microsoft.com), Mistral's Le Chat (chat.mistral.ai), Poe (poe.com) and DeepSeek (chat.deepseek.com) - the web versions you open in your browser.

Does PasteSentinel store or send my data anywhere?

No. PasteSentinel has no server. The text you paste is scanned entirely in memory, in your browser, and discarded the instant the check completes - it's never written to storage or sent anywhere, even when a secret is found. Only your on/off setting, your own ignore-list entries, and a simple detection counter are saved, locally on your device. See our Privacy Policy.

What does it actually detect?

Dozens of named formats - AWS, GitHub, Slack, Stripe, OpenAI-style, Anthropic, Google, Twilio, SendGrid, npm, GitLab, Discord and more - plus private key files (RSA, EC, OpenSSH, DSA, PKCS#8, encrypted PEM, PGP) and database connection strings with embedded passwords. Anything that doesn't match a known format but still looks like a strong, random secret is caught by a local entropy check. Your SSH .pub file is deliberately left alone, since that's meant to be shared.

Will it flag things that aren't secrets?

Rarely, but any scanner like this can have false positives on unusual-looking text. If PasteSentinel flags something you use on purpose, like a placeholder or test key, add it to your ignore list once from the extension's settings and it won't be flagged again.

When is it launching, and how much will it cost?

PasteSentinel is currently in Chrome Web Store review. It will be free with no paid tier at launch. Email us and we'll let you know the day it's live.

Is PasteSentinel affiliated with OpenAI, Anthropic, Google or the other platforms?

No. PasteSentinel is an independent tool and is not affiliated with, endorsed by, or sponsored by OpenAI, Anthropic, Google, Microsoft, Mistral AI, Quora (Poe), Perplexity AI, DeepSeek, or any other platform named on this page.

How do I contact support?

Email wisplo.support@gmail.com and we'll get back to you.