ChatDataMask: Data Leak Prevention for ChatGPT & Claude (GDPR)

ChatDataMask is a lightweight Chrome extension built for data leak prevention: it redacts personal information — names, emails, phone numbers, and more — locally through tokenization before your prompts ever reach ChatGPT or Claude. It supports your GDPR & EU AI Act workflow by keeping sensitive details out of cloud AI models in the first place. This privacy tool serves professional users — HR teams, recruiters, lawyers, copywriters, and analysts — who want to use AI safely while reducing the risk of leaks or regulatory non-compliance. 🔒 LOCAL-FIRST ARCHITECTURE The extension works as a local data-loss-prevention layer at the browser level: obfuscation, anonymization, and restoration all happen inside your Side Panel. Personal records stay on your device, never reaching external servers or AI training pipelines. 💡 PURPOSE OF THE TOOL Every time you paste client contracts, CVs, financial reports, or internal messages into cloud-based AI tools, you risk exposing confidential information. ChatDataMask acts as a secure local barrier between your private inputs and public cloud models, applying redaction automatically before you hit send. 🛠️ WHAT GETS DETECTED The extension recognizes and redacts common categories of sensitive text: contact details such as email addresses and usernames, phone numbers in international formats (powered by 'libphonenumber-js'), and physical addresses. On the financial side, it covers IBAN and SWIFT codes, bank account details, common credit card formats, and crypto wallets across Bitcoin, Ethereum, and other EVM-compatible chains. It also catches technical identifiers like IP and MAC addresses, secrets such as API keys and access tokens, and personal identifiers including full names, passport and national ID numbers, and tax or VAT registration numbers where applicable. 🚀 HOW IT WORKS - Safe Prompting: Send tokenized, anonymized prompts to AI platforms while keeping the text context readable for the model. - One-Click Restoration: Reverse the AI's response back to your original data, right inside your workflow. - Automatic Reset on Edit: Changing your input automatically clears any downstream response and result, so you never mix up old and new entries by mistake. - Guided Step Flow: The extension only lets you move forward once the current step is ready, reducing manual mistakes during processing. 🎯 WORKS Right inside the chat on ChatGPT (OpenAI), Claude (Anthropic) and Google Gemini: a shield in the chat field shows that ChatDataMask is active, sensitive details are highlighted when you paste or start a new line, and one click masks them, one by one or all at once. If unmasked details are still in your message when you press Send, ChatDataMask warns you and lets you mask them first. For other AI tools, including Microsoft Copilot, mask your text in the Side Panel, paste it into the chat, then paste the AI’s answer back to restore your real data. 🌍 GLOBAL PRIVACY STANDARDS Built around the data-minimization principles central to the EU GDPR and the EU AI Act, and mindful of consumer-privacy frameworks such as the California CCPA. ChatDataMask is a technical safeguard, not a certified compliance product — always check the fit against your own organization's data-protection policy.