Maskr - Private AI Leak Guard

Maskr checks what you're about to send to an AI chatbot and stops personal data and secrets before they leave your browser. Everything happens on your device. Maskr has no servers, no accounts and no tracking, and your prompts are never sent anywhere. WHAT IT CATCHES • Indian identity and banking details, checked properly rather than guessed: Aadhaar numbers are verified with their checksum, and PAN, GSTIN, UPI IDs, IFSC codes with account numbers, and Indian mobile and landline numbers are all recognised. • Secrets that developers paste by accident: API keys and access tokens, private keys, passwords and database connection strings. • Personal and payment details: email addresses, phone numbers and card numbers. • ID numbers from passports, driving licences and voter IDs, and the employee, patient or policy numbers people often paste by mistake. • Names, home addresses, dates of birth and health details, found by a small AI model that runs inside the extension. • Harmless look-alikes, such as format examples, meeting IDs and toll-free helplines, are recognised and left alone. ATTACHMENTS TOO • Images, PDFs and text files are checked the moment you attach them, before the chat site uploads them. • Photos and screenshots of Aadhaar and PAN cards, voter IDs, driving licences, passport pages and debit or credit cards are recognised, including bilingual cards, old and new designs, and photos taken at an angle or in poor light. Card numbers, ID numbers, names and addresses are found inside PDFs, scans and filled-in forms too. • Redact & attach: blacks out just the sensitive parts of an image and attaches the cleaned copy. That means the numbers, the names and addresses (with their Hindi copy on a bilingual card), the photo, the QR code and the signature, while the rest of the card stays readable. • Everyday files go through untouched: menus, bills, product labels, posters and screenshots don't set off alarms, and a file with only contact details, such as your own résumé, gets a warning you can click past rather than a block. • Reading happens on your device, like everything else. Faces are only located so they can be covered, never recognised. WHAT HAPPENS WHEN IT FINDS SOMETHING • High-risk data is blocked. Your prompt stays in the box so you can fix it. • Other personal data gets a warning. Edit it, or send it anyway. • Mask & send: one click replaces just the sensitive parts with placeholders like [AADHAAR] and sends the rest. The masked prompt is checked again before it goes. WORKS WHERE YOU CHAT • Works with ChatGPT, Claude, Gemini and Copilot out of the box. • You can add other AI chat sites, including chat apps you run on your own computer. Chrome asks your permission for each one. • Pause Maskr on a site for an hour, a day, or until you turn it back on. YOUR OWN DASHBOARD, ON YOUR DEVICE • An alert history with charts, search and export. It records the kind of data found, never the data itself. • Your own rules: always block, warn about, or allow any type of data, on every site or just some. • Test a prompt to see what Maskr would do. PRIVATE BY DESIGN • No data leaves your browser: no servers, analytics, ads or accounts. • History and settings live only in your browser's extension storage, and you can erase them at any time. • Free, with no daily limits. Privacy policy: https://thomasshelby4477.github.io/maskr-privacy/