Protect PDF with Password
Add AES-256 password protection to your PDF. Optionally restrict printing, copying, and editing. Files are deleted after 24 hours.
How It Works
This tool uses AES-256 encryption — the same industry-standard cipher used by Adobe Acrobat and modern PDF readers since version 9. Your file is processed on the server, encrypted, and saved back to your session. The password is used only during encryption and is never stored or logged.
Password to Open (User Password)
When enabled, the PDF requires the password before it can be viewed at all. Opening the file in any reader (Adobe, browser, mobile app) will prompt for the password. Without it, the file cannot be decrypted.
Permission Restrictions (Owner Password)
When enabled, the PDF opens freely but the selected actions (printing, copying, editing, form filling) are blocked unless the password is entered. Use this when you want the document to be readable but not modifiable.
Combine Both Modes
You can enable both modes at once. The same password is used for both — the file requires the password to open, and once opened, the restricted actions still require the password.
Privacy & Ownership
By using this tool, you confirm that you are the rightful owner of the PDF file or have authorization to modify it. All uploaded and protected files are automatically deleted after 24 hours. Files are isolated to your session and are not accessible to other users.
Frequently Asked Questions (FAQ)
Q: What encryption is used?
A: AES-256, the industry-standard cipher used by modern PDF readers (Adobe Acrobat 9 and later).
Q: Is my password stored on the server?
A: No. It is used only during encryption and discarded immediately. We never log or transmit passwords.
Q: What is the difference between open password and permission restrictions?
A: The open password blocks viewing the file at all. Permission restrictions let the file open freely but block actions like printing, copying, or editing.
Q: Can I protect a PDF that is already password-protected?
A: No. Already-protected PDFs are rejected. Remove the existing password first with a PDF unlock tool.
Q: What is the maximum file size?
A: 100 MB per file. Encryption is fast — even large PDFs are processed in a few seconds.
Q: Can I protect the same PDF multiple times with different passwords?
A: Yes. Each protected version is saved as a separate file. The original stays untouched.
Q: How strong should my password be?
A: At least 12 characters with mixed case, digits, and symbols for strong security. The strength meter shows how resistant your password is.
Q: How long are my files kept on the server?
A: All files are automatically deleted after 24 hours. You can also remove them manually from the Files page.