Find personal data in your text before you paste it into an AI
Paste text, choose your countries and see what an AI would receive if you sent it as it is. Everything runs in your browser: nothing is uploaded, and there is no account.
Countries whose national IDs to look for
Emails, phone numbers with a country code, cards and IBANs are always checked. National IDs are only checked for the countries you select, because without that, ordinary invoice numbers and dates would be mistaken for IDs.
How it decides
- Email, card (Luhn check), IBAN (mod-97 check) and international phone numbers are detected in any language.
- National IDs are validated with each country’s check digit, so a random 9-digit number is not flagged. Covered here: Chile (RUT), Spain (DNI, NIE), Mexico (CURP), Argentina (CUIT/CUIL), Brazil (CPF), Italy (codice fiscale), Netherlands (BSN), Poland (PESEL), India (Aadhaar), Canada (SIN) and the United States (SSN, only when the text says “SSN” or “Social Security”).
- The text never leaves this page. You can check that in your browser’s network tab.
What this tool does not do
- It does not recognise names, addresses or free-form details inside a paragraph.
- It does not read PDF, Word or Excel files: paste text only.
- Passport numbers and other IDs without a check digit are not covered.
- It is a demonstration of the idea, not a guarantee. Always review the result before sending anything to an AI.
Do this for whole documents, on your own PC
ContextDeck Docs converts PDF, Word, Excel and PowerPoint files and hides this kind of data on your computer before the text reaches ChatGPT, Claude or Copilot. It shows what was hidden and keeps a dated record. It reduces the risk of exposing personal data; it is not legal advice.
Download for Windows See how it works
14-day Pro trial, no card. Nothing is uploaded.
Questions
Does this tool send my text anywhere?
No. The detection runs in your browser with JavaScript. There is no server call, so nothing you paste leaves your computer.
Why do I have to choose countries?
National ID numbers are only digits with a check digit. Many ordinary numbers (invoice numbers, dates, totals) satisfy the check digit of some country. Scoping by the countries you choose avoids marking them.
Does it find names?
No. Names inside a paragraph cannot be recognised reliably by simple rules, so they are left for you to review. ContextDeck Docs lets you add client and company names once and hides them in every document.
Is this enough to comply with GDPR or other privacy laws?
No. It helps you notice some personal data before using AI, but it is not legal advice and does not replace your own review or your legal obligations.