Hides and anonymizes names, emails, cards and secrets before your prompt reaches ChatGPT, Claude or Gemini. 100% local, no servers.
Users
496
+27 in 30 days
Rating
5.0 / 5
unchanged in 30 days
Ratings
5
0 in 30 days
Store rank
#44K
#37K among extensions
Version
1.5.1
updated 17 Sep 2026
Users
monthly, 8 months
Latest, 16 Oct 2026:496 usersMove the mouse over the chart for any month
Ratings count
monthly, 8 months
Latest, 16 Oct 2026:5 ratingsMove the mouse over the chart for any month
The Chrome Web Store rounds user counts down to the leading digit, so the user line moves in steps. The ratings count is exact and is the better signal of real adoption.
About PiiBlocker: Mask & Redact Personal Data (PII) in AI Chats
STOP DATA LEAKS TO AI CHATBOTS
People run their work through AI chats now. Contracts, emails, patient notes,
spreadsheets. Everything you paste is stored on someone else's server.
PiiBlocker masks, redacts and anonymises personal data, sensitive information
and secrets before your prompt leaves your browser. Names, emails, phone numbers,
addresses, credit card numbers, Social Security numbers, National Insurance
numbers, API keys and passwords are detected as you type, replaced with
placeholders like [PERSON_A], and swapped back in the reply. The AI only ever
sees the placeholders.
Detection and masking run locally. Free mode makes zero network calls. No
account, no server, no usage limits.
Watch the 60-second demo: https://www.youtube.com/watch?v=VpYqkC-_UVg
SUPPORTED SITES
PiiBlocker works on seven AI chat platforms, all free. The extension can read
those seven sites and nothing else. See the screenshots for the full list, or
visit https://www.piiblock.com
If Chrome asks you to re-approve the extension after an update, that is
expected when a version adds protected sites. Click Enable and protection
resumes immediately.
HOW IT WORKS
1. Type normally into any supported AI chat
2. PiiBlocker highlights detected personal data in real time
3. Before sending, choose what to mask, hide or keep in a confirmation dialog
4. Critical data like credit cards, SSNs and API keys is redacted automatically
5. The AI responds with placeholders, and PiiBlocker shows you the real data
6. Missed something? Select any text and right-click to mask it manually
WHAT IT DETECTS (15+ TYPES)
Credit card numbers with validation, Social Security numbers, API keys and
secrets, passwords, names, addresses, phone numbers, emails, dates of birth,
ages, salaries, medical conditions, bank account numbers, UK National Insurance
numbers, and more.
PRIVACY BY DESIGN
Detection happens in your browser. In free mode your data never
leaves your device and the extension makes zero network calls.
AES-256 encrypted storage with auto-expiring keys.
One-click purge of all stored data.
WHO USES IT
Lawyers protecting client confidentiality. Clinicians and practice staff
keeping patient data out of AI tools. Developers redacting secrets and API
keys from prompts. Anyone who wants to use AI at work without leaking personal
information.
FEATURES
Real-time detection using NER and regex patterns.
Auto-redaction for critical data.
Right-click context menu for anything the detector missed.
Placeholders swapped back in the AI's replies.
Personal dictionary that learns your specific data.
Works on all seven supported sites.
Self-monitoring on every site, so silent breakage gets caught.
Stays protected on long-running tabs.
FREE CORE PROTECTION
Core protection is free on all supported sites, with no account and
no usage limits. An enterprise tier with managed deployment and an admin
dashboard is available at https://www.piiblock.com/enterprise
SUPPORT
Website: https://www.piiblock.com
Email: support@piiblock.com
GitHub: https://github.com/piiblocker-coder/piiblocker