Protect PDF
Add a password so only the right people can open your PDF.
or drop it here · paste with Ctrl+V
Processed on your device — files are never uploaded
to use this tool — every tool is free, with no daily limit.
Why use FilesForU's Protect PDF tool
Lock a PDF with a password using strong AES-256 encryption.
Free, no watermark
Protect PDF is free with a free account — no daily limit and no watermark on your files.
Private
Your files are processed on your own device. They are never uploaded to our servers.
Fast
No upload and no queue, so most files are ready in seconds.
Works everywhere
Use it on Windows, Mac, Linux, iPhone or Android — nothing to install.
How to use Protect PDF
- 1
Choose a PDF file
- 2
Set a password and permissions
- 3
Download the protected PDF
Questions & answers
How secure is it?
We use AES-256, the strongest standard PDF encryption, powered by the open-source qpdf engine.
What if I forget the password?
We never see or store your password, so we can't recover it. Keep it somewhere safe.
Are my files uploaded to your server?
No. This tool runs entirely inside your browser, so your files stay on your device. FilesForU never receives, stores or sees them.
Is it really free?
Yes. Every tool is free with a free account — no daily limit, no watermarks, and files up to 500 MB.