Protect PDF
Encrypt your PDF with a password. Control who can open and edit your document.
Drag your PDF here or click to choose
Single file, up to 100MB
When to Use This Tool
Password-protect your PDF when sharing sensitive documents like contracts, financial statements, or personal records. Set a password that recipients must enter before they can open the file. All encryption happens in your browser.
How to Protect PDF
- Upload your PDF file (drag & drop)
- Enter a password to open the PDF
- Optionally set an owner password for permissions control
- Click Protect PDF and download your encrypted file
Features
- RC4 128-bit encryption for strong security
- Separate user and owner passwords
- Owner password controls printing, editing permissions
- 100% browser-based processing (no uploads to servers)
- Your password never leaves your device
Things to Know
The tool uses RC4 128-bit encryption. Make sure to remember your password — there is no way to recover it if lost. Encrypted PDFs can be unlocked with our Unlock PDF tool if you know the password.
Frequently Asked Questions
What encryption does this use?
The tool applies RC4 128-bit encryption, which is widely supported by PDF readers including Adobe Acrobat, Preview, and Chrome's built-in viewer.
Can I set permissions (print, edit, copy)?
Yes. You can set an owner password that controls whether recipients can print, edit, or copy content from the PDF.
What if I forget the password?
There is no password recovery mechanism. Make sure to store your password somewhere safe. We cannot recover it because all processing happens locally in your browser.
Is my password sent to any server?
No. The password and encryption process happen entirely in your browser. Your password never leaves your device.
Built for locking sensitive documents, controlling access to contracts, and securing confidential files. Continue with Merge PDF or Watermark PDF.
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