PISIGuard: AI Chat Privacy Shield That Masks Your Data Locally
PISIGuard: Protect your personal and sensitive info when you chat with AI
PISIGuard is a browser extension that automatically detects and masks personal and sensitive information—names, emails, phone numbers, credit card numbers, passwords, API keys—before you send messages to AI chatbots like ChatGPT, Claude, and DeepSeek. It replaces sensitive data with placeholders, then restores the original values in the AI's response. All processing happens locally in your browser, so no data is sent to external servers. The extension is configurable for advanced users and available for Chrome, Edge, Firefox, and other browsers.
From your point of view, it’s mostly invisible; from the AI’s point of view, the sensitive stuff was never there.
- ddevnyc
Some people are confused as to what this is, so I thought I'd bring up this sentence from the Readme:
> PISIGuard runs entirely in your browser. It spots names, email addresses, phone numbers, credit card numbers, passwords, API keys, and more, replaces them with safe placeholders, then puts the real values back into the AI’s reply. From your point of view, it’s mostly invisible; from the AI’s point of view, the sensitive stuff was never there.
I suggest putting it at the top of the readme!
I think it's a very smart system, and could easily extend beyond AI use. Please continue working on it!
- no-name-here
Interesting.
1. Suggestion: Personally I love when projects mention whether they’ve found other existing software that does something similar, and if so how this app compares.
2. On iOS when I click into the project it opens into the GitHub iOS app but there’s a big empty box below the big logo. Clicking the box opens the video in my browser. Maybe it’s a GitHub app issue? I didn’t spend any time further on that.
3. Minor but I couldn’t be sure what pisi stands for - the page seems to use “personal and sensitive information” (PASI?) but maybe it stands for “personal information sensitive information” even if the page doesn’t use that phrase?
- stelonix
Great project! I'm looking for something like this but for code: an app that runs locally and obfuscates variables & strings into generic things, so you don't leak code/db structure to LLM companies. Couldn't find anything though so I'm using an LLM to write one.