Mask your data before it reaches the AI

Local-only PII detection and redaction for AI chatbots. Regex patterns and a local NER model run entirely in your browser-no server, no API, no telemetry.

Install from GitHub How it works
100% local
No telemetry
MIT licensed

How it works

Four steps between typing and sending-everything happens in your browser.

1

Intercept

When you hit send, PiiI intercepts the message before it leaves the page.

2

Detect

Regex patterns catch structured data. A local ONNX NER model identifies names and addresses.

3

Review & alias

See what was found, review confidence scores, and approve alias replacements.

4

Send redacted

The redacted prompt goes to the AI. Your original data stays in a local map.

Privacy model

Your data never leaves your browser. Here's how.

Local-only inference

Both regex and the NER model run entirely in your browser using onnxruntime-web (WASM). No network requests are made during detection.

One-time model download

The NER model weights download once from Hugging Face CDN. After that, everything works offline.

Local storage only

The alias map (what [NAME_1] really means) is stored in chrome.storage.local. Nothing is sent to any server.

What it detects

Ten categories of personally identifiable information, each with its own visual indicator.

Email Phone Address API Key Date URL Name SSN Credit Card

Supported platforms

Works with the AI chatbots you already use.

ChatGPT
Claude
Gemini
Copilot
Perplexity
DeepSeek

In action

PiiI integrated with popular AI chatbots.

ChatGPT redaction popup showing detected PII with alias suggestions
ChatGPT - Review and redact sensitive data before sending
Claude file upload dialog warning about PII detected in .docx file
Claude - PII detection in uploaded .docx files
Copilot chat interface with redacted prompt using alias placeholders
Copilot - Redacted prompt with alias placeholders
Gemini interface with colored highlights overlaying detected PII in input
Gemini - In-page highlight overlays for detected PII
Perplexity search interface with PII highlighted in the query box
Perplexity - PII detection in search queries
DeepSeek file upload warning showing PII types found in document
DeepSeek - File scan results before upload

Get PiiI on GitHub

Build from source, load unpacked in Chrome. It takes about two minutes.

Get PiiI on GitHub