Emailing a payslip, contract, or medical letter? A password on the PDF means an intercepted or forwarded copy is still unreadable without the key.
Password ≠ “view-only” trick
Real protection is encryption: the file’s contents are scrambled and only the password decrypts them. That’s different from a flimsy “restrict editing” flag some tools add, which any reader can ignore. Use proper encryption (AES).
How to protect a PDF step by step
- Open Protect PDF and select your file.
- Set a strong password and confirm it. Optionally set permissions (allow/deny printing, copying, editing).
- Choose AES encryption, then download the protected file.
Choosing a good password
- 12+ characters, mixed — not the recipient’s name or “1234”.
- Share the password out-of-band: tell them by message/call, never in the same email as the file.
- Store it in a password manager; if you lose it, the file is unrecoverable (that’s the point).
Privacy
Encryption happens in your browser — the file and password are never uploaded. Anything else would defeat the purpose. No signup, no watermark.
FAQ
AES-128 vs AES-256? Both are strong; 256 is the conservative choice for sensitive data.
Remove it later? Use Unlock PDF with the password.
Secure your document with Protect PDF.
Use Protect PDF: Encrypt PDFs with a password. No signup, nothing uploaded.
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